llvm-project/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp

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Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
//===- RewriteStatepointsForGC.cpp - Make GC relocations explicit ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Rewrite an existing set of gc.statepoints such that they make potential
// relocations performed by the garbage collector explicit in the IR.
//
//===----------------------------------------------------------------------===//
#include "llvm/Pass.h"
#include "llvm/Analysis/CFG.h"
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/TargetTransformInfo.h"
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#include "llvm/ADT/SetOperations.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/MapVector.h"
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/MDBuilder.h"
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#include "llvm/IR/Statepoint.h"
#include "llvm/IR/Value.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#define DEBUG_TYPE "rewrite-statepoints-for-gc"
using namespace llvm;
// Print the liveset found at the insert location
static cl::opt<bool> PrintLiveSet("spp-print-liveset", cl::Hidden,
cl::init(false));
static cl::opt<bool> PrintLiveSetSize("spp-print-liveset-size", cl::Hidden,
cl::init(false));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Print out the base pointers for debugging
static cl::opt<bool> PrintBasePointers("spp-print-base-pointers", cl::Hidden,
cl::init(false));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Cost threshold measuring when it is profitable to rematerialize value instead
// of relocating it
static cl::opt<unsigned>
RematerializationThreshold("spp-rematerialization-threshold", cl::Hidden,
cl::init(6));
#ifdef XDEBUG
static bool ClobberNonLive = true;
#else
static bool ClobberNonLive = false;
#endif
static cl::opt<bool, true> ClobberNonLiveOverride("rs4gc-clobber-non-live",
cl::location(ClobberNonLive),
cl::Hidden);
static cl::opt<bool> UseDeoptBundles("rs4gc-use-deopt-bundles", cl::Hidden,
cl::init(false));
static cl::opt<bool>
AllowStatepointWithNoDeoptInfo("rs4gc-allow-statepoint-with-no-deopt-info",
cl::Hidden, cl::init(true));
/// Should we split vectors of pointers into their individual elements? This
/// is known to be buggy, but the alternate implementation isn't yet ready.
/// This is purely to provide a debugging and dianostic hook until the vector
/// split is replaced with vector relocations.
static cl::opt<bool> UseVectorSplit("rs4gc-split-vector-values", cl::Hidden,
cl::init(false));
namespace {
struct RewriteStatepointsForGC : public ModulePass {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static char ID; // Pass identification, replacement for typeid
RewriteStatepointsForGC() : ModulePass(ID) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
initializeRewriteStatepointsForGCPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F);
bool runOnModule(Module &M) override {
bool Changed = false;
for (Function &F : M)
Changed |= runOnFunction(F);
if (Changed) {
// stripNonValidAttributes asserts that shouldRewriteStatepointsIn
// returns true for at least one function in the module. Since at least
// one function changed, we know that the precondition is satisfied.
stripNonValidAttributes(M);
}
return Changed;
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
void getAnalysisUsage(AnalysisUsage &AU) const override {
// We add and rewrite a bunch of instructions, but don't really do much
// else. We could in theory preserve a lot more analyses here.
AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<TargetTransformInfoWrapperPass>();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// The IR fed into RewriteStatepointsForGC may have had attributes implying
/// dereferenceability that are no longer valid/correct after
/// RewriteStatepointsForGC has run. This is because semantically, after
/// RewriteStatepointsForGC runs, all calls to gc.statepoint "free" the entire
/// heap. stripNonValidAttributes (conservatively) restores correctness
/// by erasing all attributes in the module that externally imply
/// dereferenceability.
/// Similar reasoning also applies to the noalias attributes. gc.statepoint
/// can touch the entire heap including noalias objects.
void stripNonValidAttributes(Module &M);
// Helpers for stripNonValidAttributes
void stripNonValidAttributesFromBody(Function &F);
void stripNonValidAttributesFromPrototype(Function &F);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
};
} // namespace
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
char RewriteStatepointsForGC::ID = 0;
ModulePass *llvm::createRewriteStatepointsForGCPass() {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
return new RewriteStatepointsForGC();
}
INITIALIZE_PASS_BEGIN(RewriteStatepointsForGC, "rewrite-statepoints-for-gc",
"Make relocations explicit at statepoints", false, false)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_END(RewriteStatepointsForGC, "rewrite-statepoints-for-gc",
"Make relocations explicit at statepoints", false, false)
namespace {
struct GCPtrLivenessData {
/// Values defined in this block.
DenseMap<BasicBlock *, DenseSet<Value *>> KillSet;
/// Values used in this block (and thus live); does not included values
/// killed within this block.
DenseMap<BasicBlock *, DenseSet<Value *>> LiveSet;
/// Values live into this basic block (i.e. used by any
/// instruction in this basic block or ones reachable from here)
DenseMap<BasicBlock *, DenseSet<Value *>> LiveIn;
/// Values live out of this basic block (i.e. live into
/// any successor block)
DenseMap<BasicBlock *, DenseSet<Value *>> LiveOut;
};
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// The type of the internal cache used inside the findBasePointers family
// of functions. From the callers perspective, this is an opaque type and
// should not be inspected.
//
// In the actual implementation this caches two relations:
// - The base relation itself (i.e. this pointer is based on that one)
// - The base defining value relation (i.e. before base_phi insertion)
// Generally, after the execution of a full findBasePointer call, only the
// base relation will remain. Internally, we add a mixture of the two
// types, then update all the second type to the first type
typedef DenseMap<Value *, Value *> DefiningValueMapTy;
typedef DenseSet<Value *> StatepointLiveSetTy;
typedef DenseMap<AssertingVH<Instruction>, AssertingVH<Value>>
RematerializedValueMapTy;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
struct PartiallyConstructedSafepointRecord {
/// The set of values known to be live across this safepoint
StatepointLiveSetTy LiveSet;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// Mapping from live pointers to a base-defining-value
DenseMap<Value *, Value *> PointerToBase;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// The *new* gc.statepoint instruction itself. This produces the token
/// that normal path gc.relocates and the gc.result are tied to.
Instruction *StatepointToken;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// Instruction to which exceptional gc relocates are attached
/// Makes it easier to iterate through them during relocationViaAlloca.
Instruction *UnwindToken;
/// Record live values we are rematerialized instead of relocating.
/// They are not included into 'LiveSet' field.
/// Maps rematerialized copy to it's original value.
RematerializedValueMapTy RematerializedValues;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
};
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static ArrayRef<Use> GetDeoptBundleOperands(ImmutableCallSite CS) {
assert(UseDeoptBundles && "Should not be called otherwise!");
Optional<OperandBundleUse> DeoptBundle = CS.getOperandBundle("deopt");
if (!DeoptBundle.hasValue()) {
assert(AllowStatepointWithNoDeoptInfo &&
"Found non-leaf call without deopt info!");
return None;
}
return DeoptBundle.getValue().Inputs;
}
/// Compute the live-in set for every basic block in the function
static void computeLiveInValues(DominatorTree &DT, Function &F,
GCPtrLivenessData &Data);
/// Given results from the dataflow liveness computation, find the set of live
/// Values at a particular instruction.
static void findLiveSetAtInst(Instruction *inst, GCPtrLivenessData &Data,
StatepointLiveSetTy &out);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// TODO: Once we can get to the GCStrategy, this becomes
// Optional<bool> isGCManagedPointer(const Type *Ty) const override {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static bool isGCPointerType(Type *T) {
if (auto *PT = dyn_cast<PointerType>(T))
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// For the sake of this example GC, we arbitrarily pick addrspace(1) as our
// GC managed heap. We know that a pointer into this heap needs to be
// updated and that no other pointer does.
return (1 == PT->getAddressSpace());
return false;
}
// Return true if this type is one which a) is a gc pointer or contains a GC
// pointer and b) is of a type this code expects to encounter as a live value.
// (The insertion code will assert that a type which matches (a) and not (b)
// is not encountered.)
static bool isHandledGCPointerType(Type *T) {
// We fully support gc pointers
if (isGCPointerType(T))
return true;
// We partially support vectors of gc pointers. The code will assert if it
// can't handle something.
if (auto VT = dyn_cast<VectorType>(T))
if (isGCPointerType(VT->getElementType()))
return true;
return false;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
#ifndef NDEBUG
/// Returns true if this type contains a gc pointer whether we know how to
/// handle that type or not.
static bool containsGCPtrType(Type *Ty) {
if (isGCPointerType(Ty))
return true;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (VectorType *VT = dyn_cast<VectorType>(Ty))
return isGCPointerType(VT->getScalarType());
if (ArrayType *AT = dyn_cast<ArrayType>(Ty))
return containsGCPtrType(AT->getElementType());
if (StructType *ST = dyn_cast<StructType>(Ty))
return std::any_of(ST->subtypes().begin(), ST->subtypes().end(),
containsGCPtrType);
return false;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Returns true if this is a type which a) is a gc pointer or contains a GC
// pointer and b) is of a type which the code doesn't expect (i.e. first class
// aggregates). Used to trip assertions.
static bool isUnhandledGCPointerType(Type *Ty) {
return containsGCPtrType(Ty) && !isHandledGCPointerType(Ty);
}
#endif
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static bool order_by_name(Value *a, Value *b) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (a->hasName() && b->hasName()) {
return -1 == a->getName().compare(b->getName());
} else if (a->hasName() && !b->hasName()) {
return true;
} else if (!a->hasName() && b->hasName()) {
return false;
} else {
// Better than nothing, but not stable
return a < b;
}
}
// Return the name of the value suffixed with the provided value, or if the
// value didn't have a name, the default value specified.
static std::string suffixed_name_or(Value *V, StringRef Suffix,
StringRef DefaultName) {
return V->hasName() ? (V->getName() + Suffix).str() : DefaultName.str();
}
// Conservatively identifies any definitions which might be live at the
// given instruction. The analysis is performed immediately before the
// given instruction. Values defined by that instruction are not considered
// live. Values used by that instruction are considered live.
static void analyzeParsePointLiveness(
DominatorTree &DT, GCPtrLivenessData &OriginalLivenessData,
const CallSite &CS, PartiallyConstructedSafepointRecord &result) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Instruction *inst = CS.getInstruction();
StatepointLiveSetTy LiveSet;
findLiveSetAtInst(inst, OriginalLivenessData, LiveSet);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (PrintLiveSet) {
// Note: This output is used by several of the test cases
// The order of elements in a set is not stable, put them in a vec and sort
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// by name
SmallVector<Value *, 64> Temp;
Temp.insert(Temp.end(), LiveSet.begin(), LiveSet.end());
std::sort(Temp.begin(), Temp.end(), order_by_name);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
errs() << "Live Variables:\n";
for (Value *V : Temp)
dbgs() << " " << V->getName() << " " << *V << "\n";
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
if (PrintLiveSetSize) {
errs() << "Safepoint For: " << CS.getCalledValue()->getName() << "\n";
errs() << "Number live values: " << LiveSet.size() << "\n";
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
result.LiveSet = LiveSet;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
static bool isKnownBaseResult(Value *V);
namespace {
/// A single base defining value - An immediate base defining value for an
/// instruction 'Def' is an input to 'Def' whose base is also a base of 'Def'.
/// For instructions which have multiple pointer [vector] inputs or that
/// transition between vector and scalar types, there is no immediate base
/// defining value. The 'base defining value' for 'Def' is the transitive
/// closure of this relation stopping at the first instruction which has no
/// immediate base defining value. The b.d.v. might itself be a base pointer,
/// but it can also be an arbitrary derived pointer.
struct BaseDefiningValueResult {
/// Contains the value which is the base defining value.
Value * const BDV;
/// True if the base defining value is also known to be an actual base
/// pointer.
const bool IsKnownBase;
BaseDefiningValueResult(Value *BDV, bool IsKnownBase)
: BDV(BDV), IsKnownBase(IsKnownBase) {
#ifndef NDEBUG
// Check consistency between new and old means of checking whether a BDV is
// a base.
bool MustBeBase = isKnownBaseResult(BDV);
assert(!MustBeBase || MustBeBase == IsKnownBase);
#endif
}
};
}
static BaseDefiningValueResult findBaseDefiningValue(Value *I);
/// Return a base defining value for the 'Index' element of the given vector
/// instruction 'I'. If Index is null, returns a BDV for the entire vector
/// 'I'. As an optimization, this method will try to determine when the
/// element is known to already be a base pointer. If this can be established,
/// the second value in the returned pair will be true. Note that either a
/// vector or a pointer typed value can be returned. For the former, the
/// vector returned is a BDV (and possibly a base) of the entire vector 'I'.
/// If the later, the return pointer is a BDV (or possibly a base) for the
/// particular element in 'I'.
static BaseDefiningValueResult
findBaseDefiningValueOfVector(Value *I) {
// Each case parallels findBaseDefiningValue below, see that code for
// detailed motivation.
if (isa<Argument>(I))
// An incoming argument to the function is a base pointer
return BaseDefiningValueResult(I, true);
if (isa<Constant>(I))
// Constant vectors consist only of constant pointers.
return BaseDefiningValueResult(I, true);
if (isa<LoadInst>(I))
return BaseDefiningValueResult(I, true);
if (isa<InsertElementInst>(I))
// We don't know whether this vector contains entirely base pointers or
// not. To be conservatively correct, we treat it as a BDV and will
// duplicate code as needed to construct a parallel vector of bases.
return BaseDefiningValueResult(I, false);
if (isa<ShuffleVectorInst>(I))
// We don't know whether this vector contains entirely base pointers or
// not. To be conservatively correct, we treat it as a BDV and will
// duplicate code as needed to construct a parallel vector of bases.
// TODO: There a number of local optimizations which could be applied here
// for particular sufflevector patterns.
return BaseDefiningValueResult(I, false);
// A PHI or Select is a base defining value. The outer findBasePointer
// algorithm is responsible for constructing a base value for this BDV.
assert((isa<SelectInst>(I) || isa<PHINode>(I)) &&
"unknown vector instruction - no base found for vector element");
return BaseDefiningValueResult(I, false);
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// Helper function for findBasePointer - Will return a value which either a)
/// defines the base pointer for the input, b) blocks the simple search
/// (i.e. a PHI or Select of two derived pointers), or c) involves a change
/// from pointer to vector type or back.
static BaseDefiningValueResult findBaseDefiningValue(Value *I) {
assert(I->getType()->isPtrOrPtrVectorTy() &&
"Illegal to ask for the base pointer of a non-pointer type");
if (I->getType()->isVectorTy())
return findBaseDefiningValueOfVector(I);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (isa<Argument>(I))
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// An incoming argument to the function is a base pointer
// We should have never reached here if this argument isn't an gc value
return BaseDefiningValueResult(I, true);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (isa<Constant>(I))
// We assume that objects with a constant base (e.g. a global) can't move
// and don't need to be reported to the collector because they are always
// live. All constants have constant bases. Besides global references, all
// kinds of constants (e.g. undef, constant expressions, null pointers) can
// be introduced by the inliner or the optimizer, especially on dynamically
// dead paths. See e.g. test4 in constants.ll.
return BaseDefiningValueResult(I, true);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (CastInst *CI = dyn_cast<CastInst>(I)) {
Value *Def = CI->stripPointerCasts();
// If stripping pointer casts changes the address space there is an
// addrspacecast in between.
assert(cast<PointerType>(Def->getType())->getAddressSpace() ==
cast<PointerType>(CI->getType())->getAddressSpace() &&
"unsupported addrspacecast");
// If we find a cast instruction here, it means we've found a cast which is
// not simply a pointer cast (i.e. an inttoptr). We don't know how to
// handle int->ptr conversion.
assert(!isa<CastInst>(Def) && "shouldn't find another cast here");
return findBaseDefiningValue(Def);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
if (isa<LoadInst>(I))
// The value loaded is an gc base itself
return BaseDefiningValueResult(I, true);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(I))
// The base of this GEP is the base
return findBaseDefiningValue(GEP->getPointerOperand());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
switch (II->getIntrinsicID()) {
default:
// fall through to general call handling
break;
case Intrinsic::experimental_gc_statepoint:
llvm_unreachable("statepoints don't produce pointers");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
case Intrinsic::experimental_gc_relocate: {
// Rerunning safepoint insertion after safepoints are already
// inserted is not supported. It could probably be made to work,
// but why are you doing this? There's no good reason.
llvm_unreachable("repeat safepoint insertion is not supported");
}
case Intrinsic::gcroot:
// Currently, this mechanism hasn't been extended to work with gcroot.
// There's no reason it couldn't be, but I haven't thought about the
// implications much.
llvm_unreachable(
"interaction with the gcroot mechanism is not supported");
}
}
// We assume that functions in the source language only return base
// pointers. This should probably be generalized via attributes to support
// both source language and internal functions.
if (isa<CallInst>(I) || isa<InvokeInst>(I))
return BaseDefiningValueResult(I, true);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// I have absolutely no idea how to implement this part yet. It's not
// necessarily hard, I just haven't really looked at it yet.
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert(!isa<LandingPadInst>(I) && "Landing Pad is unimplemented");
if (isa<AtomicCmpXchgInst>(I))
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// A CAS is effectively a atomic store and load combined under a
// predicate. From the perspective of base pointers, we just treat it
// like a load.
return BaseDefiningValueResult(I, true);
assert(!isa<AtomicRMWInst>(I) && "Xchg handled above, all others are "
"binary ops which don't apply to pointers");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// The aggregate ops. Aggregates can either be in the heap or on the
// stack, but in either case, this is simply a field load. As a result,
// this is a defining definition of the base just like a load is.
if (isa<ExtractValueInst>(I))
return BaseDefiningValueResult(I, true);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// We should never see an insert vector since that would require we be
// tracing back a struct value not a pointer value.
assert(!isa<InsertValueInst>(I) &&
"Base pointer for a struct is meaningless");
// An extractelement produces a base result exactly when it's input does.
// We may need to insert a parallel instruction to extract the appropriate
// element out of the base vector corresponding to the input. Given this,
// it's analogous to the phi and select case even though it's not a merge.
if (isa<ExtractElementInst>(I))
// Note: There a lot of obvious peephole cases here. This are deliberately
// handled after the main base pointer inference algorithm to make writing
// test cases to exercise that code easier.
return BaseDefiningValueResult(I, false);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// The last two cases here don't return a base pointer. Instead, they
// return a value which dynamically selects from among several base
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// derived pointers (each with it's own base potentially). It's the job of
// the caller to resolve these.
assert((isa<SelectInst>(I) || isa<PHINode>(I)) &&
"missing instruction case in findBaseDefiningValing");
return BaseDefiningValueResult(I, false);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// Returns the base defining value for this value.
static Value *findBaseDefiningValueCached(Value *I, DefiningValueMapTy &Cache) {
Value *&Cached = Cache[I];
if (!Cached) {
Cached = findBaseDefiningValue(I).BDV;
DEBUG(dbgs() << "fBDV-cached: " << I->getName() << " -> "
<< Cached->getName() << "\n");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
assert(Cache[I] != nullptr);
return Cached;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// Return a base pointer for this value if known. Otherwise, return it's
/// base defining value.
static Value *findBaseOrBDV(Value *I, DefiningValueMapTy &Cache) {
Value *Def = findBaseDefiningValueCached(I, Cache);
auto Found = Cache.find(Def);
if (Found != Cache.end()) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Either a base-of relation, or a self reference. Caller must check.
return Found->second;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Only a BDV available
return Def;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// Given the result of a call to findBaseDefiningValue, or findBaseOrBDV,
/// is it known to be a base pointer? Or do we need to continue searching.
static bool isKnownBaseResult(Value *V) {
if (!isa<PHINode>(V) && !isa<SelectInst>(V) &&
!isa<ExtractElementInst>(V) && !isa<InsertElementInst>(V) &&
!isa<ShuffleVectorInst>(V)) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// no recursion possible
return true;
}
if (isa<Instruction>(V) &&
cast<Instruction>(V)->getMetadata("is_base_value")) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// This is a previously inserted base phi or select. We know
// that this is a base value.
return true;
}
// We need to keep searching
return false;
}
namespace {
/// Models the state of a single base defining value in the findBasePointer
/// algorithm for determining where a new instruction is needed to propagate
/// the base of this BDV.
class BDVState {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
public:
enum Status { Unknown, Base, Conflict };
BDVState(Status s, Value *b = nullptr) : status(s), base(b) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert(status != Base || b);
}
explicit BDVState(Value *b) : status(Base), base(b) {}
BDVState() : status(Unknown), base(nullptr) {}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Status getStatus() const { return status; }
Value *getBase() const { return base; }
bool isBase() const { return getStatus() == Base; }
bool isUnknown() const { return getStatus() == Unknown; }
bool isConflict() const { return getStatus() == Conflict; }
bool operator==(const BDVState &other) const {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
return base == other.base && status == other.status;
}
bool operator!=(const BDVState &other) const { return !(*this == other); }
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
LLVM_DUMP_METHOD
void dump() const { print(dbgs()); dbgs() << '\n'; }
void print(raw_ostream &OS) const {
switch (status) {
case Unknown:
OS << "U";
break;
case Base:
OS << "B";
break;
case Conflict:
OS << "C";
break;
};
OS << " (" << base << " - "
<< (base ? base->getName() : "nullptr") << "): ";
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
private:
Status status;
AssertingVH<Value> base; // non null only if status == base
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
};
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#ifndef NDEBUG
static raw_ostream &operator<<(raw_ostream &OS, const BDVState &State) {
State.print(OS);
return OS;
}
#endif
namespace {
// Values of type BDVState form a lattice, and this is a helper
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// class that implementes the meet operation. The meat of the meet
// operation is implemented in MeetBDVStates::pureMeet
class MeetBDVStates {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
public:
/// Initializes the currentResult to the TOP state so that if can be met with
/// any other state to produce that state.
MeetBDVStates() {}
// Destructively meet the current result with the given BDVState
void meetWith(BDVState otherState) {
currentResult = meet(otherState, currentResult);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
BDVState getResult() const { return currentResult; }
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
private:
BDVState currentResult;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// Perform a meet operation on two elements of the BDVState lattice.
static BDVState meet(BDVState LHS, BDVState RHS) {
assert((pureMeet(LHS, RHS) == pureMeet(RHS, LHS)) &&
"math is wrong: meet does not commute!");
BDVState Result = pureMeet(LHS, RHS);
DEBUG(dbgs() << "meet of " << LHS << " with " << RHS
<< " produced " << Result << "\n");
return Result;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
static BDVState pureMeet(const BDVState &stateA, const BDVState &stateB) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
switch (stateA.getStatus()) {
case BDVState::Unknown:
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
return stateB;
case BDVState::Base:
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert(stateA.getBase() && "can't be null");
if (stateB.isUnknown())
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
return stateA;
if (stateB.isBase()) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (stateA.getBase() == stateB.getBase()) {
assert(stateA == stateB && "equality broken!");
return stateA;
}
return BDVState(BDVState::Conflict);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
assert(stateB.isConflict() && "only three states!");
return BDVState(BDVState::Conflict);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
case BDVState::Conflict:
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
return stateA;
}
llvm_unreachable("only three states!");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
};
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// For a given value or instruction, figure out what base ptr it's derived
/// from. For gc objects, this is simply itself. On success, returns a value
/// which is the base pointer. (This is reliable and can be used for
/// relocation.) On failure, returns nullptr.
static Value *findBasePointer(Value *I, DefiningValueMapTy &cache) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Value *def = findBaseOrBDV(I, cache);
if (isKnownBaseResult(def)) {
return def;
}
// Here's the rough algorithm:
// - For every SSA value, construct a mapping to either an actual base
// pointer or a PHI which obscures the base pointer.
// - Construct a mapping from PHI to unknown TOP state. Use an
// optimistic algorithm to propagate base pointer information. Lattice
// looks like:
// UNKNOWN
// b1 b2 b3 b4
// CONFLICT
// When algorithm terminates, all PHIs will either have a single concrete
// base or be in a conflict state.
// - For every conflict, insert a dummy PHI node without arguments. Add
// these to the base[Instruction] = BasePtr mapping. For every
// non-conflict, add the actual base.
// - For every conflict, add arguments for the base[a] of each input
// arguments.
//
// Note: A simpler form of this would be to add the conflict form of all
// PHIs without running the optimistic algorithm. This would be
// analogous to pessimistic data flow and would likely lead to an
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// overall worse solution.
#ifndef NDEBUG
auto isExpectedBDVType = [](Value *BDV) {
return isa<PHINode>(BDV) || isa<SelectInst>(BDV) ||
isa<ExtractElementInst>(BDV) || isa<InsertElementInst>(BDV);
};
#endif
// Once populated, will contain a mapping from each potentially non-base BDV
// to a lattice value (described above) which corresponds to that BDV.
// We use the order of insertion (DFS over the def/use graph) to provide a
// stable deterministic ordering for visiting DenseMaps (which are unordered)
// below. This is important for deterministic compilation.
MapVector<Value *, BDVState> States;
// Recursively fill in all base defining values reachable from the initial
// one for which we don't already know a definite base value for
/* scope */ {
SmallVector<Value*, 16> Worklist;
Worklist.push_back(def);
States.insert(std::make_pair(def, BDVState()));
while (!Worklist.empty()) {
Value *Current = Worklist.pop_back_val();
assert(!isKnownBaseResult(Current) && "why did it get added?");
auto visitIncomingValue = [&](Value *InVal) {
Value *Base = findBaseOrBDV(InVal, cache);
if (isKnownBaseResult(Base))
// Known bases won't need new instructions introduced and can be
// ignored safely
return;
assert(isExpectedBDVType(Base) && "the only non-base values "
"we see should be base defining values");
if (States.insert(std::make_pair(Base, BDVState())).second)
Worklist.push_back(Base);
};
if (PHINode *Phi = dyn_cast<PHINode>(Current)) {
for (Value *InVal : Phi->incoming_values())
visitIncomingValue(InVal);
} else if (SelectInst *Sel = dyn_cast<SelectInst>(Current)) {
visitIncomingValue(Sel->getTrueValue());
visitIncomingValue(Sel->getFalseValue());
} else if (auto *EE = dyn_cast<ExtractElementInst>(Current)) {
visitIncomingValue(EE->getVectorOperand());
} else if (auto *IE = dyn_cast<InsertElementInst>(Current)) {
visitIncomingValue(IE->getOperand(0)); // vector operand
visitIncomingValue(IE->getOperand(1)); // scalar operand
} else {
// There is one known class of instructions we know we don't handle.
assert(isa<ShuffleVectorInst>(Current));
llvm_unreachable("unimplemented instruction case");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
}
#ifndef NDEBUG
DEBUG(dbgs() << "States after initialization:\n");
for (auto Pair : States) {
DEBUG(dbgs() << " " << Pair.second << " for " << *Pair.first << "\n");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
#endif
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Return a phi state for a base defining value. We'll generate a new
// base state for known bases and expect to find a cached state otherwise.
auto getStateForBDV = [&](Value *baseValue) {
if (isKnownBaseResult(baseValue))
return BDVState(baseValue);
auto I = States.find(baseValue);
assert(I != States.end() && "lookup failed!");
return I->second;
};
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
bool progress = true;
while (progress) {
#ifndef NDEBUG
const size_t oldSize = States.size();
#endif
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
progress = false;
// We're only changing values in this loop, thus safe to keep iterators.
// Since this is computing a fixed point, the order of visit does not
// effect the result. TODO: We could use a worklist here and make this run
// much faster.
for (auto Pair : States) {
Value *BDV = Pair.first;
assert(!isKnownBaseResult(BDV) && "why did it get added?");
// Given an input value for the current instruction, return a BDVState
// instance which represents the BDV of that value.
auto getStateForInput = [&](Value *V) mutable {
Value *BDV = findBaseOrBDV(V, cache);
return getStateForBDV(BDV);
};
MeetBDVStates calculateMeet;
if (SelectInst *select = dyn_cast<SelectInst>(BDV)) {
calculateMeet.meetWith(getStateForInput(select->getTrueValue()));
calculateMeet.meetWith(getStateForInput(select->getFalseValue()));
} else if (PHINode *Phi = dyn_cast<PHINode>(BDV)) {
for (Value *Val : Phi->incoming_values())
calculateMeet.meetWith(getStateForInput(Val));
} else if (auto *EE = dyn_cast<ExtractElementInst>(BDV)) {
// The 'meet' for an extractelement is slightly trivial, but it's still
// useful in that it drives us to conflict if our input is.
calculateMeet.meetWith(getStateForInput(EE->getVectorOperand()));
} else {
// Given there's a inherent type mismatch between the operands, will
// *always* produce Conflict.
auto *IE = cast<InsertElementInst>(BDV);
calculateMeet.meetWith(getStateForInput(IE->getOperand(0)));
calculateMeet.meetWith(getStateForInput(IE->getOperand(1)));
}
BDVState oldState = States[BDV];
BDVState newState = calculateMeet.getResult();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (oldState != newState) {
progress = true;
States[BDV] = newState;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
assert(oldSize == States.size() &&
"fixed point shouldn't be adding any new nodes to state");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
#ifndef NDEBUG
DEBUG(dbgs() << "States after meet iteration:\n");
for (auto Pair : States) {
DEBUG(dbgs() << " " << Pair.second << " for " << *Pair.first << "\n");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
#endif
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Insert Phis for all conflicts
// TODO: adjust naming patterns to avoid this order of iteration dependency
for (auto Pair : States) {
Instruction *I = cast<Instruction>(Pair.first);
BDVState State = Pair.second;
assert(!isKnownBaseResult(I) && "why did it get added?");
assert(!State.isUnknown() && "Optimistic algorithm didn't complete!");
// extractelement instructions are a bit special in that we may need to
// insert an extract even when we know an exact base for the instruction.
// The problem is that we need to convert from a vector base to a scalar
// base for the particular indice we're interested in.
if (State.isBase() && isa<ExtractElementInst>(I) &&
isa<VectorType>(State.getBase()->getType())) {
auto *EE = cast<ExtractElementInst>(I);
// TODO: In many cases, the new instruction is just EE itself. We should
// exploit this, but can't do it here since it would break the invariant
// about the BDV not being known to be a base.
auto *BaseInst = ExtractElementInst::Create(State.getBase(),
EE->getIndexOperand(),
"base_ee", EE);
BaseInst->setMetadata("is_base_value", MDNode::get(I->getContext(), {}));
States[I] = BDVState(BDVState::Base, BaseInst);
}
// Since we're joining a vector and scalar base, they can never be the
// same. As a result, we should always see insert element having reached
// the conflict state.
if (isa<InsertElementInst>(I)) {
assert(State.isConflict());
}
if (!State.isConflict())
continue;
/// Create and insert a new instruction which will represent the base of
/// the given instruction 'I'.
auto MakeBaseInstPlaceholder = [](Instruction *I) -> Instruction* {
if (isa<PHINode>(I)) {
BasicBlock *BB = I->getParent();
int NumPreds = std::distance(pred_begin(BB), pred_end(BB));
assert(NumPreds > 0 && "how did we reach here");
std::string Name = suffixed_name_or(I, ".base", "base_phi");
return PHINode::Create(I->getType(), NumPreds, Name, I);
} else if (SelectInst *Sel = dyn_cast<SelectInst>(I)) {
// The undef will be replaced later
UndefValue *Undef = UndefValue::get(Sel->getType());
std::string Name = suffixed_name_or(I, ".base", "base_select");
return SelectInst::Create(Sel->getCondition(), Undef,
Undef, Name, Sel);
} else if (auto *EE = dyn_cast<ExtractElementInst>(I)) {
UndefValue *Undef = UndefValue::get(EE->getVectorOperand()->getType());
std::string Name = suffixed_name_or(I, ".base", "base_ee");
return ExtractElementInst::Create(Undef, EE->getIndexOperand(), Name,
EE);
} else {
auto *IE = cast<InsertElementInst>(I);
UndefValue *VecUndef = UndefValue::get(IE->getOperand(0)->getType());
UndefValue *ScalarUndef = UndefValue::get(IE->getOperand(1)->getType());
std::string Name = suffixed_name_or(I, ".base", "base_ie");
return InsertElementInst::Create(VecUndef, ScalarUndef,
IE->getOperand(2), Name, IE);
}
};
Instruction *BaseInst = MakeBaseInstPlaceholder(I);
// Add metadata marking this as a base value
BaseInst->setMetadata("is_base_value", MDNode::get(I->getContext(), {}));
States[I] = BDVState(BDVState::Conflict, BaseInst);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Returns a instruction which produces the base pointer for a given
// instruction. The instruction is assumed to be an input to one of the BDVs
// seen in the inference algorithm above. As such, we must either already
// know it's base defining value is a base, or have inserted a new
// instruction to propagate the base of it's BDV and have entered that newly
// introduced instruction into the state table. In either case, we are
// assured to be able to determine an instruction which produces it's base
// pointer.
auto getBaseForInput = [&](Value *Input, Instruction *InsertPt) {
Value *BDV = findBaseOrBDV(Input, cache);
Value *Base = nullptr;
if (isKnownBaseResult(BDV)) {
Base = BDV;
} else {
// Either conflict or base.
assert(States.count(BDV));
Base = States[BDV].getBase();
}
assert(Base && "can't be null");
// The cast is needed since base traversal may strip away bitcasts
if (Base->getType() != Input->getType() &&
InsertPt) {
Base = new BitCastInst(Base, Input->getType(), "cast",
InsertPt);
}
return Base;
};
// Fixup all the inputs of the new PHIs. Visit order needs to be
// deterministic and predictable because we're naming newly created
// instructions.
for (auto Pair : States) {
Instruction *BDV = cast<Instruction>(Pair.first);
BDVState State = Pair.second;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert(!isKnownBaseResult(BDV) && "why did it get added?");
assert(!State.isUnknown() && "Optimistic algorithm didn't complete!");
if (!State.isConflict())
continue;
if (PHINode *basephi = dyn_cast<PHINode>(State.getBase())) {
PHINode *phi = cast<PHINode>(BDV);
unsigned NumPHIValues = phi->getNumIncomingValues();
for (unsigned i = 0; i < NumPHIValues; i++) {
Value *InVal = phi->getIncomingValue(i);
BasicBlock *InBB = phi->getIncomingBlock(i);
// If we've already seen InBB, add the same incoming value
// we added for it earlier. The IR verifier requires phi
// nodes with multiple entries from the same basic block
// to have the same incoming value for each of those
// entries. If we don't do this check here and basephi
// has a different type than base, we'll end up adding two
// bitcasts (and hence two distinct values) as incoming
// values for the same basic block.
int blockIndex = basephi->getBasicBlockIndex(InBB);
if (blockIndex != -1) {
Value *oldBase = basephi->getIncomingValue(blockIndex);
basephi->addIncoming(oldBase, InBB);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#ifndef NDEBUG
Value *Base = getBaseForInput(InVal, nullptr);
// In essence this assert states: the only way two
// values incoming from the same basic block may be
// different is by being different bitcasts of the same
// value. A cleanup that remains TODO is changing
// findBaseOrBDV to return an llvm::Value of the correct
// type (and still remain pure). This will remove the
// need to add bitcasts.
assert(Base->stripPointerCasts() == oldBase->stripPointerCasts() &&
"sanity -- findBaseOrBDV should be pure!");
#endif
continue;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Find the instruction which produces the base for each input. We may
// need to insert a bitcast in the incoming block.
// TODO: Need to split critical edges if insertion is needed
Value *Base = getBaseForInput(InVal, InBB->getTerminator());
basephi->addIncoming(Base, InBB);
}
assert(basephi->getNumIncomingValues() == NumPHIValues);
} else if (SelectInst *BaseSel = dyn_cast<SelectInst>(State.getBase())) {
SelectInst *Sel = cast<SelectInst>(BDV);
// Operand 1 & 2 are true, false path respectively. TODO: refactor to
// something more safe and less hacky.
for (int i = 1; i <= 2; i++) {
Value *InVal = Sel->getOperand(i);
// Find the instruction which produces the base for each input. We may
// need to insert a bitcast.
Value *Base = getBaseForInput(InVal, BaseSel);
BaseSel->setOperand(i, Base);
}
} else if (auto *BaseEE = dyn_cast<ExtractElementInst>(State.getBase())) {
Value *InVal = cast<ExtractElementInst>(BDV)->getVectorOperand();
// Find the instruction which produces the base for each input. We may
// need to insert a bitcast.
Value *Base = getBaseForInput(InVal, BaseEE);
BaseEE->setOperand(0, Base);
} else {
auto *BaseIE = cast<InsertElementInst>(State.getBase());
auto *BdvIE = cast<InsertElementInst>(BDV);
auto UpdateOperand = [&](int OperandIdx) {
Value *InVal = BdvIE->getOperand(OperandIdx);
Value *Base = getBaseForInput(InVal, BaseIE);
BaseIE->setOperand(OperandIdx, Base);
};
UpdateOperand(0); // vector operand
UpdateOperand(1); // scalar operand
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
// Now that we're done with the algorithm, see if we can optimize the
// results slightly by reducing the number of new instructions needed.
// Arguably, this should be integrated into the algorithm above, but
// doing as a post process step is easier to reason about for the moment.
DenseMap<Value *, Value *> ReverseMap;
SmallPtrSet<Instruction *, 16> NewInsts;
SmallSetVector<AssertingVH<Instruction>, 16> Worklist;
// Note: We need to visit the states in a deterministic order. We uses the
// Keys we sorted above for this purpose. Note that we are papering over a
// bigger problem with the algorithm above - it's visit order is not
// deterministic. A larger change is needed to fix this.
for (auto Pair : States) {
auto *BDV = Pair.first;
auto State = Pair.second;
Value *Base = State.getBase();
assert(BDV && Base);
assert(!isKnownBaseResult(BDV) && "why did it get added?");
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
assert(isKnownBaseResult(Base) &&
"must be something we 'know' is a base pointer");
if (!State.isConflict())
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
continue;
ReverseMap[Base] = BDV;
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
if (auto *BaseI = dyn_cast<Instruction>(Base)) {
NewInsts.insert(BaseI);
Worklist.insert(BaseI);
}
}
auto ReplaceBaseInstWith = [&](Value *BDV, Instruction *BaseI,
Value *Replacement) {
// Add users which are new instructions (excluding self references)
for (User *U : BaseI->users())
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
if (auto *UI = dyn_cast<Instruction>(U))
if (NewInsts.count(UI) && UI != BaseI)
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
Worklist.insert(UI);
// Then do the actual replacement
NewInsts.erase(BaseI);
ReverseMap.erase(BaseI);
BaseI->replaceAllUsesWith(Replacement);
assert(States.count(BDV));
assert(States[BDV].isConflict() && States[BDV].getBase() == BaseI);
States[BDV] = BDVState(BDVState::Conflict, Replacement);
BaseI->eraseFromParent();
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
};
const DataLayout &DL = cast<Instruction>(def)->getModule()->getDataLayout();
while (!Worklist.empty()) {
Instruction *BaseI = Worklist.pop_back_val();
assert(NewInsts.count(BaseI));
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
Value *Bdv = ReverseMap[BaseI];
if (auto *BdvI = dyn_cast<Instruction>(Bdv))
if (BaseI->isIdenticalTo(BdvI)) {
DEBUG(dbgs() << "Identical Base: " << *BaseI << "\n");
ReplaceBaseInstWith(Bdv, BaseI, Bdv);
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
continue;
}
if (Value *V = SimplifyInstruction(BaseI, DL)) {
DEBUG(dbgs() << "Base " << *BaseI << " simplified to " << *V << "\n");
ReplaceBaseInstWith(Bdv, BaseI, V);
[RewriteStatepointsForGC] Reduce the number of new instructions for base pointers When computing base pointers, we introduce new instructions to propagate the base of existing instructions which might not be bases. However, the algorithm doesn't make any effort to recognize when the new instruction to be inserted is the same as an existing one already in the IR. Since this is happening immediately before rewriting, we don't really have a chance to fix it after the pass runs without teaching loop passes about statepoints. I'm really not thrilled with this patch. I've rewritten it 4 different ways now, but this is the best I've come up with. The case where the new instruction is just the original base defining value could be merged into the existing algorithm with some complexity. The problem is that we might have something like an extractelement from a phi of two vectors. It may be trivially obvious that the base of the 0th element is an existing instruction, but I can't see how to make the algorithm itself figure that out. Thus, I resort to the call to SimplifyInstruction instead. Note that we can only adjust the instructions we've inserted ourselves. The live sets are still being tracked in side structures at this point in the code. We can't easily muck with instructions which might be in them. Long term, I'm really thinking we need to materialize the live pointer sets explicitly in the IR somehow rather than using side structures to track them. Differential Revision: http://reviews.llvm.org/D12004 llvm-svn: 246133
2015-08-27 09:02:28 +08:00
continue;
}
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Cache all of our results so we can cheaply reuse them
// NOTE: This is actually two caches: one of the base defining value
// relation and one of the base pointer relation! FIXME
for (auto Pair : States) {
auto *BDV = Pair.first;
Value *base = Pair.second.getBase();
assert(BDV && base);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
std::string fromstr = cache.count(BDV) ? cache[BDV]->getName() : "none";
DEBUG(dbgs() << "Updating base value cache"
<< " for: " << BDV->getName()
<< " from: " << fromstr
<< " to: " << base->getName() << "\n");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (cache.count(BDV)) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Once we transition from the BDV relation being store in the cache to
// the base relation being stored, it must be stable
assert((!isKnownBaseResult(cache[BDV]) || cache[BDV] == base) &&
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
"base relation should be stable");
}
cache[BDV] = base;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
assert(cache.count(def));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
return cache[def];
}
// For a set of live pointers (base and/or derived), identify the base
// pointer of the object which they are derived from. This routine will
// mutate the IR graph as needed to make the 'base' pointer live at the
// definition site of 'derived'. This ensures that any use of 'derived' can
// also use 'base'. This may involve the insertion of a number of
// additional PHI nodes.
//
// preconditions: live is a set of pointer type Values
//
// side effects: may insert PHI nodes into the existing CFG, will preserve
// CFG, will not remove or mutate any existing nodes
//
// post condition: PointerToBase contains one (derived, base) pair for every
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// pointer in live. Note that derived can be equal to base if the original
// pointer was a base pointer.
static void
findBasePointers(const StatepointLiveSetTy &live,
DenseMap<Value *, Value *> &PointerToBase,
DominatorTree *DT, DefiningValueMapTy &DVCache) {
// For the naming of values inserted to be deterministic - which makes for
// much cleaner and more stable tests - we need to assign an order to the
// live values. DenseSets do not provide a deterministic order across runs.
SmallVector<Value *, 64> Temp;
Temp.insert(Temp.end(), live.begin(), live.end());
std::sort(Temp.begin(), Temp.end(), order_by_name);
for (Value *ptr : Temp) {
Value *base = findBasePointer(ptr, DVCache);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert(base && "failed to find base pointer");
PointerToBase[ptr] = base;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert((!isa<Instruction>(base) || !isa<Instruction>(ptr) ||
DT->dominates(cast<Instruction>(base)->getParent(),
cast<Instruction>(ptr)->getParent())) &&
"The base we found better dominate the derived pointer");
// If you see this trip and like to live really dangerously, the code should
// be correct, just with idioms the verifier can't handle. You can try
// disabling the verifier at your own substantial risk.
assert(!isa<ConstantPointerNull>(base) &&
"the relocation code needs adjustment to handle the relocation of "
"a null pointer constant without causing false positives in the "
"safepoint ir verifier.");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
/// Find the required based pointers (and adjust the live set) for the given
/// parse point.
static void findBasePointers(DominatorTree &DT, DefiningValueMapTy &DVCache,
const CallSite &CS,
PartiallyConstructedSafepointRecord &result) {
DenseMap<Value *, Value *> PointerToBase;
findBasePointers(result.LiveSet, PointerToBase, &DT, DVCache);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (PrintBasePointers) {
// Note: Need to print these in a stable order since this is checked in
// some tests.
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
errs() << "Base Pairs (w/o Relocation):\n";
SmallVector<Value *, 64> Temp;
Temp.reserve(PointerToBase.size());
for (auto Pair : PointerToBase) {
Temp.push_back(Pair.first);
}
std::sort(Temp.begin(), Temp.end(), order_by_name);
for (Value *Ptr : Temp) {
Value *Base = PointerToBase[Ptr];
errs() << " derived ";
Ptr->printAsOperand(errs(), false);
errs() << " base ";
Base->printAsOperand(errs(), false);
errs() << "\n";;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
result.PointerToBase = PointerToBase;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// Given an updated version of the dataflow liveness results, update the
/// liveset and base pointer maps for the call site CS.
static void recomputeLiveInValues(GCPtrLivenessData &RevisedLivenessData,
const CallSite &CS,
PartiallyConstructedSafepointRecord &result);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static void recomputeLiveInValues(
Function &F, DominatorTree &DT, ArrayRef<CallSite> toUpdate,
MutableArrayRef<struct PartiallyConstructedSafepointRecord> records) {
// TODO-PERF: reuse the original liveness, then simply run the dataflow
// again. The old values are still live and will help it stabilize quickly.
GCPtrLivenessData RevisedLivenessData;
computeLiveInValues(DT, F, RevisedLivenessData);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (size_t i = 0; i < records.size(); i++) {
struct PartiallyConstructedSafepointRecord &info = records[i];
const CallSite &CS = toUpdate[i];
recomputeLiveInValues(RevisedLivenessData, CS, info);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
// When inserting gc.relocate and gc.result calls, we need to ensure there are
// no uses of the original value / return value between the gc.statepoint and
// the gc.relocate / gc.result call. One case which can arise is a phi node
// starting one of the successor blocks. We also need to be able to insert the
// gc.relocates only on the path which goes through the statepoint. We might
// need to split an edge to make this possible.
static BasicBlock *
normalizeForInvokeSafepoint(BasicBlock *BB, BasicBlock *InvokeParent,
DominatorTree &DT) {
BasicBlock *Ret = BB;
if (!BB->getUniquePredecessor())
Ret = SplitBlockPredecessors(BB, InvokeParent, "", &DT);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Now that 'Ret' has unique predecessor we can safely remove all phi nodes
// from it
FoldSingleEntryPHINodes(Ret);
assert(!isa<PHINode>(Ret->begin()) &&
"All PHI nodes should have been removed!");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// At this point, we can safely insert a gc.relocate or gc.result as the first
// instruction in Ret if needed.
return Ret;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Create new attribute set containing only attributes which can be transferred
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// from original call to the safepoint.
static AttributeSet legalizeCallAttributes(AttributeSet AS) {
AttributeSet Ret;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (unsigned Slot = 0; Slot < AS.getNumSlots(); Slot++) {
unsigned Index = AS.getSlotIndex(Slot);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (Index == AttributeSet::ReturnIndex ||
Index == AttributeSet::FunctionIndex) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (Attribute Attr : make_range(AS.begin(Slot), AS.end(Slot))) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Do not allow certain attributes - just skip them
// Safepoint can not be read only or read none.
if (Attr.hasAttribute(Attribute::ReadNone) ||
Attr.hasAttribute(Attribute::ReadOnly))
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
continue;
// These attributes control the generation of the gc.statepoint call /
// invoke itself; and once the gc.statepoint is in place, they're of no
// use.
if (Attr.hasAttribute("statepoint-num-patch-bytes") ||
Attr.hasAttribute("statepoint-id"))
continue;
Ret = Ret.addAttributes(
AS.getContext(), Index,
AttributeSet::get(AS.getContext(), Index, AttrBuilder(Attr)));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
// Just skip parameter attributes for now
}
return Ret;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// Helper function to place all gc relocates necessary for the given
/// statepoint.
/// Inputs:
/// liveVariables - list of variables to be relocated.
/// liveStart - index of the first live variable.
/// basePtrs - base pointers.
/// statepointToken - statepoint instruction to which relocates should be
/// bound.
/// Builder - Llvm IR builder to be used to construct new calls.
static void CreateGCRelocates(ArrayRef<Value *> LiveVariables,
const int LiveStart,
ArrayRef<Value *> BasePtrs,
Instruction *StatepointToken,
IRBuilder<> Builder) {
if (LiveVariables.empty())
return;
auto FindIndex = [](ArrayRef<Value *> LiveVec, Value *Val) {
auto ValIt = std::find(LiveVec.begin(), LiveVec.end(), Val);
assert(ValIt != LiveVec.end() && "Val not found in LiveVec!");
size_t Index = std::distance(LiveVec.begin(), ValIt);
assert(Index < LiveVec.size() && "Bug in std::find?");
return Index;
};
Module *M = StatepointToken->getModule();
[rs4gc] Optionally directly relocated vector of pointers This patch teaches rewrite-statepoints-for-gc to relocate vector-of-pointers directly rather than trying to split them. This builds on the recent lowering/IR changes to allow vector typed gc.relocates. The motivation for this is that we recently found a bug in the vector splitting code where depending on visit order, a vector might not be relocated at some safepoint. Specifically, the bug is that the splitting code wasn't updating the side tables (live vector) of other safepoints. As a result, a vector which was live at two safepoints might not be updated at one of them. However, if you happened to visit safepoints in post order over the dominator tree, everything worked correctly. Weirdly, it turns out that post order is actually an incredibly common order to visit instructions in in practice. Frustratingly, I have not managed to write a test case which actually hits this. I can only reproduce it in large IR files produced by actual applications. Rather than continue to make this code more complicated, we can remove all of the complexity by just representing the relocation of the entire vector natively in the IR. At the moment, the new functionality is hidden behind a flag. To use this code, you need to pass "-rs4gc-split-vector-values=0". Once I have a chance to stress test with this option and get feedback from other users, my plan is to flip the default and remove the original splitting code. I would just remove it now, but given the rareness of the bug, I figured it was better to leave it in place until the new approach has been stress tested. Differential Revision: http://reviews.llvm.org/D15982 llvm-svn: 257244
2016-01-09 09:31:13 +08:00
// All gc_relocate are generated as i8 addrspace(1)* (or a vector type whose
// element type is i8 addrspace(1)*). We originally generated unique
// declarations for each pointer type, but this proved problematic because
// the intrinsic mangling code is incomplete and fragile. Since we're moving
// towards a single unified pointer type anyways, we can just cast everything
// to an i8* of the right address space. A bitcast is added later to convert
// gc_relocate to the actual value's type.
auto getGCRelocateDecl = [&] (Type *Ty) {
assert(isHandledGCPointerType(Ty));
auto AS = Ty->getScalarType()->getPointerAddressSpace();
Type *NewTy = Type::getInt8PtrTy(M->getContext(), AS);
if (auto *VT = dyn_cast<VectorType>(Ty))
NewTy = VectorType::get(NewTy, VT->getNumElements());
return Intrinsic::getDeclaration(M, Intrinsic::experimental_gc_relocate,
{NewTy});
};
// Lazily populated map from input types to the canonicalized form mentioned
// in the comment above. This should probably be cached somewhere more
// broadly.
DenseMap<Type*, Value*> TypeToDeclMap;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (unsigned i = 0; i < LiveVariables.size(); i++) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Generate the gc.relocate call and save the result
Value *BaseIdx =
Builder.getInt32(LiveStart + FindIndex(LiveVariables, BasePtrs[i]));
Value *LiveIdx = Builder.getInt32(LiveStart + i);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
[rs4gc] Optionally directly relocated vector of pointers This patch teaches rewrite-statepoints-for-gc to relocate vector-of-pointers directly rather than trying to split them. This builds on the recent lowering/IR changes to allow vector typed gc.relocates. The motivation for this is that we recently found a bug in the vector splitting code where depending on visit order, a vector might not be relocated at some safepoint. Specifically, the bug is that the splitting code wasn't updating the side tables (live vector) of other safepoints. As a result, a vector which was live at two safepoints might not be updated at one of them. However, if you happened to visit safepoints in post order over the dominator tree, everything worked correctly. Weirdly, it turns out that post order is actually an incredibly common order to visit instructions in in practice. Frustratingly, I have not managed to write a test case which actually hits this. I can only reproduce it in large IR files produced by actual applications. Rather than continue to make this code more complicated, we can remove all of the complexity by just representing the relocation of the entire vector natively in the IR. At the moment, the new functionality is hidden behind a flag. To use this code, you need to pass "-rs4gc-split-vector-values=0". Once I have a chance to stress test with this option and get feedback from other users, my plan is to flip the default and remove the original splitting code. I would just remove it now, but given the rareness of the bug, I figured it was better to leave it in place until the new approach has been stress tested. Differential Revision: http://reviews.llvm.org/D15982 llvm-svn: 257244
2016-01-09 09:31:13 +08:00
Type *Ty = LiveVariables[i]->getType();
if (!TypeToDeclMap.count(Ty))
TypeToDeclMap[Ty] = getGCRelocateDecl(Ty);
Value *GCRelocateDecl = TypeToDeclMap[Ty];
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// only specify a debug name if we can give a useful one
CallInst *Reloc = Builder.CreateCall(
GCRelocateDecl, {StatepointToken, BaseIdx, LiveIdx},
suffixed_name_or(LiveVariables[i], ".relocated", ""));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Trick CodeGen into thinking there are lots of free registers at this
// fake call.
Reloc->setCallingConv(CallingConv::Cold);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
namespace {
/// This struct is used to defer RAUWs and `eraseFromParent` s. Using this
/// avoids having to worry about keeping around dangling pointers to Values.
class DeferredReplacement {
AssertingVH<Instruction> Old;
AssertingVH<Instruction> New;
public:
explicit DeferredReplacement(Instruction *Old, Instruction *New) :
Old(Old), New(New) {
assert(Old != New && "Not allowed!");
}
/// Does the task represented by this instance.
void doReplacement() {
Instruction *OldI = Old;
Instruction *NewI = New;
assert(OldI != NewI && "Disallowed at construction?!");
Old = nullptr;
New = nullptr;
if (NewI)
OldI->replaceAllUsesWith(NewI);
OldI->eraseFromParent();
}
};
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static void
makeStatepointExplicitImpl(const CallSite CS, /* to replace */
const SmallVectorImpl<Value *> &BasePtrs,
const SmallVectorImpl<Value *> &LiveVariables,
PartiallyConstructedSafepointRecord &Result,
std::vector<DeferredReplacement> &Replacements) {
assert(BasePtrs.size() == LiveVariables.size());
assert((UseDeoptBundles || isStatepoint(CS)) &&
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
"This method expects to be rewriting a statepoint");
// Then go ahead and use the builder do actually do the inserts. We insert
// immediately before the previous instruction under the assumption that all
// arguments will be available here. We can't insert afterwards since we may
// be replacing a terminator.
Instruction *InsertBefore = CS.getInstruction();
IRBuilder<> Builder(InsertBefore);
ArrayRef<Value *> GCArgs(LiveVariables);
uint64_t StatepointID = 0xABCDEF00;
uint32_t NumPatchBytes = 0;
uint32_t Flags = uint32_t(StatepointFlags::None);
ArrayRef<Use> CallArgs;
ArrayRef<Use> DeoptArgs;
ArrayRef<Use> TransitionArgs;
Value *CallTarget = nullptr;
if (UseDeoptBundles) {
CallArgs = {CS.arg_begin(), CS.arg_end()};
DeoptArgs = GetDeoptBundleOperands(CS);
if (auto TransitionBundle =
CS.getOperandBundle(LLVMContext::OB_gc_transition)) {
Flags |= uint32_t(StatepointFlags::GCTransition);
TransitionArgs = TransitionBundle->Inputs;
}
AttributeSet OriginalAttrs = CS.getAttributes();
Attribute AttrID = OriginalAttrs.getAttribute(AttributeSet::FunctionIndex,
"statepoint-id");
if (AttrID.isStringAttribute())
AttrID.getValueAsString().getAsInteger(10, StatepointID);
Attribute AttrNumPatchBytes = OriginalAttrs.getAttribute(
AttributeSet::FunctionIndex, "statepoint-num-patch-bytes");
if (AttrNumPatchBytes.isStringAttribute())
AttrNumPatchBytes.getValueAsString().getAsInteger(10, NumPatchBytes);
CallTarget = CS.getCalledValue();
} else {
// This branch will be gone soon, and we will soon only support the
// UseDeoptBundles == true configuration.
Statepoint OldSP(CS);
StatepointID = OldSP.getID();
NumPatchBytes = OldSP.getNumPatchBytes();
Flags = OldSP.getFlags();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
CallArgs = {OldSP.arg_begin(), OldSP.arg_end()};
DeoptArgs = {OldSP.vm_state_begin(), OldSP.vm_state_end()};
TransitionArgs = {OldSP.gc_transition_args_begin(),
OldSP.gc_transition_args_end()};
CallTarget = OldSP.getCalledValue();
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Create the statepoint given all the arguments
Instruction *Token = nullptr;
AttributeSet ReturnAttrs;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (CS.isCall()) {
CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
CallInst *Call = Builder.CreateGCStatepointCall(
StatepointID, NumPatchBytes, CallTarget, Flags, CallArgs,
TransitionArgs, DeoptArgs, GCArgs, "safepoint_token");
Call->setTailCall(ToReplace->isTailCall());
Call->setCallingConv(ToReplace->getCallingConv());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Currently we will fail on parameter attributes and on certain
// function attributes.
AttributeSet NewAttrs = legalizeCallAttributes(ToReplace->getAttributes());
// In case if we can handle this set of attributes - set up function attrs
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// directly on statepoint and return attrs later for gc_result intrinsic.
Call->setAttributes(NewAttrs.getFnAttributes());
ReturnAttrs = NewAttrs.getRetAttributes();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Token = Call;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Put the following gc_result and gc_relocate calls immediately after the
// the old call (which we're about to delete)
assert(ToReplace->getNextNode() && "Not a terminator, must have next!");
Builder.SetInsertPoint(ToReplace->getNextNode());
Builder.SetCurrentDebugLocation(ToReplace->getNextNode()->getDebugLoc());
} else {
InvokeInst *ToReplace = cast<InvokeInst>(CS.getInstruction());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Insert the new invoke into the old block. We'll remove the old one in a
// moment at which point this will become the new terminator for the
// original block.
InvokeInst *Invoke = Builder.CreateGCStatepointInvoke(
StatepointID, NumPatchBytes, CallTarget, ToReplace->getNormalDest(),
ToReplace->getUnwindDest(), Flags, CallArgs, TransitionArgs, DeoptArgs,
GCArgs, "statepoint_token");
Invoke->setCallingConv(ToReplace->getCallingConv());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Currently we will fail on parameter attributes and on certain
// function attributes.
AttributeSet NewAttrs = legalizeCallAttributes(ToReplace->getAttributes());
// In case if we can handle this set of attributes - set up function attrs
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// directly on statepoint and return attrs later for gc_result intrinsic.
Invoke->setAttributes(NewAttrs.getFnAttributes());
ReturnAttrs = NewAttrs.getRetAttributes();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Token = Invoke;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Generate gc relocates in exceptional path
BasicBlock *UnwindBlock = ToReplace->getUnwindDest();
assert(!isa<PHINode>(UnwindBlock->begin()) &&
UnwindBlock->getUniquePredecessor() &&
"can't safely insert in this block!");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Builder.SetInsertPoint(&*UnwindBlock->getFirstInsertionPt());
Builder.SetCurrentDebugLocation(ToReplace->getDebugLoc());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Attach exceptional gc relocates to the landingpad.
Instruction *ExceptionalToken = UnwindBlock->getLandingPadInst();
Result.UnwindToken = ExceptionalToken;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
const unsigned LiveStartIdx = Statepoint(Token).gcArgsStartIdx();
CreateGCRelocates(LiveVariables, LiveStartIdx, BasePtrs, ExceptionalToken,
Builder);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Generate gc relocates and returns for normal block
BasicBlock *NormalDest = ToReplace->getNormalDest();
assert(!isa<PHINode>(NormalDest->begin()) &&
NormalDest->getUniquePredecessor() &&
"can't safely insert in this block!");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Builder.SetInsertPoint(&*NormalDest->getFirstInsertionPt());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// gc relocates will be generated later as if it were regular call
// statepoint
}
assert(Token && "Should be set in one of the above branches!");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (UseDeoptBundles) {
Token->setName("statepoint_token");
if (!CS.getType()->isVoidTy() && !CS.getInstruction()->use_empty()) {
StringRef Name =
CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "";
CallInst *GCResult = Builder.CreateGCResult(Token, CS.getType(), Name);
GCResult->setAttributes(CS.getAttributes().getRetAttributes());
// We cannot RAUW or delete CS.getInstruction() because it could be in the
// live set of some other safepoint, in which case that safepoint's
// PartiallyConstructedSafepointRecord will hold a raw pointer to this
// llvm::Instruction. Instead, we defer the replacement and deletion to
// after the live sets have been made explicit in the IR, and we no longer
// have raw pointers to worry about.
Replacements.emplace_back(CS.getInstruction(), GCResult);
} else {
Replacements.emplace_back(CS.getInstruction(), nullptr);
}
} else {
assert(!CS.getInstruction()->hasNUsesOrMore(2) &&
"only valid use before rewrite is gc.result");
assert(!CS.getInstruction()->hasOneUse() ||
isGCResult(cast<Instruction>(*CS.getInstruction()->user_begin())));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Take the name of the original statepoint token if there was one.
Token->takeName(CS.getInstruction());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Update the gc.result of the original statepoint (if any) to use the newly
// inserted statepoint. This is safe to do here since the token can't be
// considered a live reference.
CS.getInstruction()->replaceAllUsesWith(Token);
CS.getInstruction()->eraseFromParent();
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Result.StatepointToken = Token;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Second, create a gc.relocate for every live variable
const unsigned LiveStartIdx = Statepoint(Token).gcArgsStartIdx();
CreateGCRelocates(LiveVariables, LiveStartIdx, BasePtrs, Token, Builder);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
namespace {
struct NameOrdering {
Value *Base;
Value *Derived;
bool operator()(NameOrdering const &a, NameOrdering const &b) {
return -1 == a.Derived->getName().compare(b.Derived->getName());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
};
}
static void StabilizeOrder(SmallVectorImpl<Value *> &BaseVec,
SmallVectorImpl<Value *> &LiveVec) {
assert(BaseVec.size() == LiveVec.size());
SmallVector<NameOrdering, 64> Temp;
for (size_t i = 0; i < BaseVec.size(); i++) {
NameOrdering v;
v.Base = BaseVec[i];
v.Derived = LiveVec[i];
Temp.push_back(v);
}
std::sort(Temp.begin(), Temp.end(), NameOrdering());
for (size_t i = 0; i < BaseVec.size(); i++) {
BaseVec[i] = Temp[i].Base;
LiveVec[i] = Temp[i].Derived;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
// Replace an existing gc.statepoint with a new one and a set of gc.relocates
// which make the relocations happening at this safepoint explicit.
//
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// WARNING: Does not do any fixup to adjust users of the original live
// values. That's the callers responsibility.
static void
makeStatepointExplicit(DominatorTree &DT, const CallSite &CS,
PartiallyConstructedSafepointRecord &Result,
std::vector<DeferredReplacement> &Replacements) {
const auto &LiveSet = Result.LiveSet;
const auto &PointerToBase = Result.PointerToBase;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Convert to vector for efficient cross referencing.
SmallVector<Value *, 64> BaseVec, LiveVec;
LiveVec.reserve(LiveSet.size());
BaseVec.reserve(LiveSet.size());
for (Value *L : LiveSet) {
LiveVec.push_back(L);
assert(PointerToBase.count(L));
Value *Base = PointerToBase.find(L)->second;
BaseVec.push_back(Base);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
assert(LiveVec.size() == BaseVec.size());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// To make the output IR slightly more stable (for use in diffs), ensure a
// fixed order of the values in the safepoint (by sorting the value name).
// The order is otherwise meaningless.
StabilizeOrder(BaseVec, LiveVec);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Do the actual rewriting and delete the old statepoint
makeStatepointExplicitImpl(CS, BaseVec, LiveVec, Result, Replacements);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Helper function for the relocationViaAlloca.
//
// It receives iterator to the statepoint gc relocates and emits a store to the
// assigned location (via allocaMap) for the each one of them. It adds the
// visited values into the visitedLiveValues set, which we will later use them
// for sanity checking.
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static void
insertRelocationStores(iterator_range<Value::user_iterator> GCRelocs,
DenseMap<Value *, Value *> &AllocaMap,
DenseSet<Value *> &VisitedLiveValues) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (User *U : GCRelocs) {
GCRelocateInst *Relocate = dyn_cast<GCRelocateInst>(U);
if (!Relocate)
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
continue;
Value *OriginalValue = const_cast<Value *>(Relocate->getDerivedPtr());
assert(AllocaMap.count(OriginalValue));
Value *Alloca = AllocaMap[OriginalValue];
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Emit store into the related alloca
// All gc_relocates are i8 addrspace(1)* typed, and it must be bitcasted to
// the correct type according to alloca.
assert(Relocate->getNextNode() &&
"Should always have one since it's not a terminator");
IRBuilder<> Builder(Relocate->getNextNode());
Value *CastedRelocatedValue =
Builder.CreateBitCast(Relocate,
cast<AllocaInst>(Alloca)->getAllocatedType(),
suffixed_name_or(Relocate, ".casted", ""));
StoreInst *Store = new StoreInst(CastedRelocatedValue, Alloca);
Store->insertAfter(cast<Instruction>(CastedRelocatedValue));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#ifndef NDEBUG
VisitedLiveValues.insert(OriginalValue);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#endif
}
}
// Helper function for the "relocationViaAlloca". Similar to the
// "insertRelocationStores" but works for rematerialized values.
static void
insertRematerializationStores(
RematerializedValueMapTy RematerializedValues,
DenseMap<Value *, Value *> &AllocaMap,
DenseSet<Value *> &VisitedLiveValues) {
for (auto RematerializedValuePair: RematerializedValues) {
Instruction *RematerializedValue = RematerializedValuePair.first;
Value *OriginalValue = RematerializedValuePair.second;
assert(AllocaMap.count(OriginalValue) &&
"Can not find alloca for rematerialized value");
Value *Alloca = AllocaMap[OriginalValue];
StoreInst *Store = new StoreInst(RematerializedValue, Alloca);
Store->insertAfter(RematerializedValue);
#ifndef NDEBUG
VisitedLiveValues.insert(OriginalValue);
#endif
}
}
/// Do all the relocation update via allocas and mem2reg
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static void relocationViaAlloca(
Function &F, DominatorTree &DT, ArrayRef<Value *> Live,
ArrayRef<PartiallyConstructedSafepointRecord> Records) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#ifndef NDEBUG
// record initial number of (static) allocas; we'll check we have the same
// number when we get done.
int InitialAllocaNum = 0;
for (auto I = F.getEntryBlock().begin(), E = F.getEntryBlock().end(); I != E;
I++)
if (isa<AllocaInst>(*I))
InitialAllocaNum++;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#endif
// TODO-PERF: change data structures, reserve
DenseMap<Value *, Value *> AllocaMap;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
SmallVector<AllocaInst *, 200> PromotableAllocas;
// Used later to chack that we have enough allocas to store all values
std::size_t NumRematerializedValues = 0;
PromotableAllocas.reserve(Live.size());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Emit alloca for "LiveValue" and record it in "allocaMap" and
// "PromotableAllocas"
auto emitAllocaFor = [&](Value *LiveValue) {
AllocaInst *Alloca = new AllocaInst(LiveValue->getType(), "",
F.getEntryBlock().getFirstNonPHI());
AllocaMap[LiveValue] = Alloca;
PromotableAllocas.push_back(Alloca);
};
// Emit alloca for each live gc pointer
for (Value *V : Live)
emitAllocaFor(V);
// Emit allocas for rematerialized values
for (const auto &Info : Records)
for (auto RematerializedValuePair : Info.RematerializedValues) {
Value *OriginalValue = RematerializedValuePair.second;
if (AllocaMap.count(OriginalValue) != 0)
continue;
emitAllocaFor(OriginalValue);
++NumRematerializedValues;
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// The next two loops are part of the same conceptual operation. We need to
// insert a store to the alloca after the original def and at each
// redefinition. We need to insert a load before each use. These are split
// into distinct loops for performance reasons.
// Update gc pointer after each statepoint: either store a relocated value or
// null (if no relocated value was found for this gc pointer and it is not a
// gc_result). This must happen before we update the statepoint with load of
// alloca otherwise we lose the link between statepoint and old def.
for (const auto &Info : Records) {
Value *Statepoint = Info.StatepointToken;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// This will be used for consistency check
DenseSet<Value *> VisitedLiveValues;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Insert stores for normal statepoint gc relocates
insertRelocationStores(Statepoint->users(), AllocaMap, VisitedLiveValues);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// In case if it was invoke statepoint
// we will insert stores for exceptional path gc relocates.
if (isa<InvokeInst>(Statepoint)) {
insertRelocationStores(Info.UnwindToken->users(), AllocaMap,
VisitedLiveValues);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Do similar thing with rematerialized values
insertRematerializationStores(Info.RematerializedValues, AllocaMap,
VisitedLiveValues);
if (ClobberNonLive) {
// As a debugging aid, pretend that an unrelocated pointer becomes null at
// the gc.statepoint. This will turn some subtle GC problems into
// slightly easier to debug SEGVs. Note that on large IR files with
// lots of gc.statepoints this is extremely costly both memory and time
// wise.
SmallVector<AllocaInst *, 64> ToClobber;
for (auto Pair : AllocaMap) {
Value *Def = Pair.first;
AllocaInst *Alloca = cast<AllocaInst>(Pair.second);
// This value was relocated
if (VisitedLiveValues.count(Def)) {
continue;
}
ToClobber.push_back(Alloca);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
auto InsertClobbersAt = [&](Instruction *IP) {
for (auto *AI : ToClobber) {
auto PT = cast<PointerType>(AI->getAllocatedType());
Constant *CPN = ConstantPointerNull::get(PT);
StoreInst *Store = new StoreInst(CPN, AI);
Store->insertBefore(IP);
}
};
// Insert the clobbering stores. These may get intermixed with the
// gc.results and gc.relocates, but that's fine.
if (auto II = dyn_cast<InvokeInst>(Statepoint)) {
InsertClobbersAt(&*II->getNormalDest()->getFirstInsertionPt());
InsertClobbersAt(&*II->getUnwindDest()->getFirstInsertionPt());
} else {
InsertClobbersAt(cast<Instruction>(Statepoint)->getNextNode());
}
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Update use with load allocas and add store for gc_relocated.
for (auto Pair : AllocaMap) {
Value *Def = Pair.first;
Value *Alloca = Pair.second;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// We pre-record the uses of allocas so that we dont have to worry about
// later update that changes the user information..
SmallVector<Instruction *, 20> Uses;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// PERF: trade a linear scan for repeated reallocation
Uses.reserve(std::distance(Def->user_begin(), Def->user_end()));
for (User *U : Def->users()) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (!isa<ConstantExpr>(U)) {
// If the def has a ConstantExpr use, then the def is either a
// ConstantExpr use itself or null. In either case
// (recursively in the first, directly in the second), the oop
// it is ultimately dependent on is null and this particular
// use does not need to be fixed up.
Uses.push_back(cast<Instruction>(U));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
std::sort(Uses.begin(), Uses.end());
auto Last = std::unique(Uses.begin(), Uses.end());
Uses.erase(Last, Uses.end());
for (Instruction *Use : Uses) {
if (isa<PHINode>(Use)) {
PHINode *Phi = cast<PHINode>(Use);
for (unsigned i = 0; i < Phi->getNumIncomingValues(); i++) {
if (Def == Phi->getIncomingValue(i)) {
LoadInst *Load = new LoadInst(
Alloca, "", Phi->getIncomingBlock(i)->getTerminator());
Phi->setIncomingValue(i, Load);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
} else {
LoadInst *Load = new LoadInst(Alloca, "", Use);
Use->replaceUsesOfWith(Def, Load);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
// Emit store for the initial gc value. Store must be inserted after load,
// otherwise store will be in alloca's use list and an extra load will be
// inserted before it.
StoreInst *Store = new StoreInst(Def, Alloca);
if (Instruction *Inst = dyn_cast<Instruction>(Def)) {
if (InvokeInst *Invoke = dyn_cast<InvokeInst>(Inst)) {
// InvokeInst is a TerminatorInst so the store need to be inserted
// into its normal destination block.
BasicBlock *NormalDest = Invoke->getNormalDest();
Store->insertBefore(NormalDest->getFirstNonPHI());
} else {
assert(!Inst->isTerminator() &&
"The only TerminatorInst that can produce a value is "
"InvokeInst which is handled above.");
Store->insertAfter(Inst);
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
} else {
assert(isa<Argument>(Def));
Store->insertAfter(cast<Instruction>(Alloca));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
assert(PromotableAllocas.size() == Live.size() + NumRematerializedValues &&
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
"we must have the same allocas with lives");
if (!PromotableAllocas.empty()) {
// Apply mem2reg to promote alloca to SSA
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
PromoteMemToReg(PromotableAllocas, DT);
}
#ifndef NDEBUG
for (auto &I : F.getEntryBlock())
if (isa<AllocaInst>(I))
InitialAllocaNum--;
assert(InitialAllocaNum == 0 && "We must not introduce any extra allocas");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#endif
}
/// Implement a unique function which doesn't require we sort the input
/// vector. Doing so has the effect of changing the output of a couple of
/// tests in ways which make them less useful in testing fused safepoints.
template <typename T> static void unique_unsorted(SmallVectorImpl<T> &Vec) {
SmallSet<T, 8> Seen;
Vec.erase(std::remove_if(Vec.begin(), Vec.end(), [&](const T &V) {
return !Seen.insert(V).second;
}), Vec.end());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
/// Insert holders so that each Value is obviously live through the entire
/// lifetime of the call.
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
static void insertUseHolderAfter(CallSite &CS, const ArrayRef<Value *> Values,
SmallVectorImpl<CallInst *> &Holders) {
if (Values.empty())
// No values to hold live, might as well not insert the empty holder
return;
Module *M = CS.getInstruction()->getModule();
// Use a dummy vararg function to actually hold the values live
Function *Func = cast<Function>(M->getOrInsertFunction(
"__tmp_use", FunctionType::get(Type::getVoidTy(M->getContext()), true)));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (CS.isCall()) {
// For call safepoints insert dummy calls right after safepoint
Holders.push_back(CallInst::Create(Func, Values, "",
&*++CS.getInstruction()->getIterator()));
return;
}
// For invoke safepooints insert dummy calls both in normal and
// exceptional destination blocks
auto *II = cast<InvokeInst>(CS.getInstruction());
Holders.push_back(CallInst::Create(
Func, Values, "", &*II->getNormalDest()->getFirstInsertionPt()));
Holders.push_back(CallInst::Create(
Func, Values, "", &*II->getUnwindDest()->getFirstInsertionPt()));
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
static void findLiveReferences(
Function &F, DominatorTree &DT, ArrayRef<CallSite> toUpdate,
MutableArrayRef<struct PartiallyConstructedSafepointRecord> records) {
GCPtrLivenessData OriginalLivenessData;
computeLiveInValues(DT, F, OriginalLivenessData);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (size_t i = 0; i < records.size(); i++) {
struct PartiallyConstructedSafepointRecord &info = records[i];
const CallSite &CS = toUpdate[i];
analyzeParsePointLiveness(DT, OriginalLivenessData, CS, info);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
/// Remove any vector of pointers from the live set by scalarizing them over the
/// statepoint instruction. Adds the scalarized pieces to the live set. It
/// would be preferable to include the vector in the statepoint itself, but
/// the lowering code currently does not handle that. Extending it would be
/// slightly non-trivial since it requires a format change. Given how rare
/// such cases are (for the moment?) scalarizing is an acceptable compromise.
static void splitVectorValues(Instruction *StatepointInst,
StatepointLiveSetTy &LiveSet,
DenseMap<Value *, Value *>& PointerToBase,
DominatorTree &DT) {
SmallVector<Value *, 16> ToSplit;
for (Value *V : LiveSet)
if (isa<VectorType>(V->getType()))
ToSplit.push_back(V);
if (ToSplit.empty())
return;
DenseMap<Value *, SmallVector<Value *, 16>> ElementMapping;
Function &F = *(StatepointInst->getParent()->getParent());
DenseMap<Value *, AllocaInst *> AllocaMap;
// First is normal return, second is exceptional return (invoke only)
DenseMap<Value *, std::pair<Value *, Value *>> Replacements;
for (Value *V : ToSplit) {
AllocaInst *Alloca =
new AllocaInst(V->getType(), "", F.getEntryBlock().getFirstNonPHI());
AllocaMap[V] = Alloca;
VectorType *VT = cast<VectorType>(V->getType());
IRBuilder<> Builder(StatepointInst);
SmallVector<Value *, 16> Elements;
for (unsigned i = 0; i < VT->getNumElements(); i++)
Elements.push_back(Builder.CreateExtractElement(V, Builder.getInt32(i)));
ElementMapping[V] = Elements;
auto InsertVectorReform = [&](Instruction *IP) {
Builder.SetInsertPoint(IP);
Builder.SetCurrentDebugLocation(IP->getDebugLoc());
Value *ResultVec = UndefValue::get(VT);
for (unsigned i = 0; i < VT->getNumElements(); i++)
ResultVec = Builder.CreateInsertElement(ResultVec, Elements[i],
Builder.getInt32(i));
return ResultVec;
};
if (isa<CallInst>(StatepointInst)) {
BasicBlock::iterator Next(StatepointInst);
Next++;
Instruction *IP = &*(Next);
Replacements[V].first = InsertVectorReform(IP);
Replacements[V].second = nullptr;
} else {
InvokeInst *Invoke = cast<InvokeInst>(StatepointInst);
// We've already normalized - check that we don't have shared destination
// blocks
BasicBlock *NormalDest = Invoke->getNormalDest();
assert(!isa<PHINode>(NormalDest->begin()));
BasicBlock *UnwindDest = Invoke->getUnwindDest();
assert(!isa<PHINode>(UnwindDest->begin()));
// Insert insert element sequences in both successors
Instruction *IP = &*(NormalDest->getFirstInsertionPt());
Replacements[V].first = InsertVectorReform(IP);
IP = &*(UnwindDest->getFirstInsertionPt());
Replacements[V].second = InsertVectorReform(IP);
}
}
for (Value *V : ToSplit) {
AllocaInst *Alloca = AllocaMap[V];
// Capture all users before we start mutating use lists
SmallVector<Instruction *, 16> Users;
for (User *U : V->users())
Users.push_back(cast<Instruction>(U));
for (Instruction *I : Users) {
if (auto Phi = dyn_cast<PHINode>(I)) {
for (unsigned i = 0; i < Phi->getNumIncomingValues(); i++)
if (V == Phi->getIncomingValue(i)) {
LoadInst *Load = new LoadInst(
Alloca, "", Phi->getIncomingBlock(i)->getTerminator());
Phi->setIncomingValue(i, Load);
}
} else {
LoadInst *Load = new LoadInst(Alloca, "", I);
I->replaceUsesOfWith(V, Load);
}
}
// Store the original value and the replacement value into the alloca
StoreInst *Store = new StoreInst(V, Alloca);
if (auto I = dyn_cast<Instruction>(V))
Store->insertAfter(I);
else
Store->insertAfter(Alloca);
// Normal return for invoke, or call return
Instruction *Replacement = cast<Instruction>(Replacements[V].first);
(new StoreInst(Replacement, Alloca))->insertAfter(Replacement);
// Unwind return for invoke only
Replacement = cast_or_null<Instruction>(Replacements[V].second);
if (Replacement)
(new StoreInst(Replacement, Alloca))->insertAfter(Replacement);
}
// apply mem2reg to promote alloca to SSA
SmallVector<AllocaInst *, 16> Allocas;
for (Value *V : ToSplit)
Allocas.push_back(AllocaMap[V]);
PromoteMemToReg(Allocas, DT);
// Update our tracking of live pointers and base mappings to account for the
// changes we just made.
for (Value *V : ToSplit) {
auto &Elements = ElementMapping[V];
LiveSet.erase(V);
LiveSet.insert(Elements.begin(), Elements.end());
// We need to update the base mapping as well.
assert(PointerToBase.count(V));
Value *OldBase = PointerToBase[V];
auto &BaseElements = ElementMapping[OldBase];
PointerToBase.erase(V);
assert(Elements.size() == BaseElements.size());
for (unsigned i = 0; i < Elements.size(); i++) {
Value *Elem = Elements[i];
PointerToBase[Elem] = BaseElements[i];
}
}
}
// Helper function for the "rematerializeLiveValues". It walks use chain
// starting from the "CurrentValue" until it meets "BaseValue". Only "simple"
// values are visited (currently it is GEP's and casts). Returns true if it
// successfully reached "BaseValue" and false otherwise.
// Fills "ChainToBase" array with all visited values. "BaseValue" is not
// recorded.
static bool findRematerializableChainToBasePointer(
SmallVectorImpl<Instruction*> &ChainToBase,
Value *CurrentValue, Value *BaseValue) {
// We have found a base value
if (CurrentValue == BaseValue) {
return true;
}
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(CurrentValue)) {
ChainToBase.push_back(GEP);
return findRematerializableChainToBasePointer(ChainToBase,
GEP->getPointerOperand(),
BaseValue);
}
if (CastInst *CI = dyn_cast<CastInst>(CurrentValue)) {
if (!CI->isNoopCast(CI->getModule()->getDataLayout()))
return false;
ChainToBase.push_back(CI);
return findRematerializableChainToBasePointer(ChainToBase,
CI->getOperand(0), BaseValue);
}
// Not supported instruction in the chain
return false;
}
// Helper function for the "rematerializeLiveValues". Compute cost of the use
// chain we are going to rematerialize.
static unsigned
chainToBasePointerCost(SmallVectorImpl<Instruction*> &Chain,
TargetTransformInfo &TTI) {
unsigned Cost = 0;
for (Instruction *Instr : Chain) {
if (CastInst *CI = dyn_cast<CastInst>(Instr)) {
assert(CI->isNoopCast(CI->getModule()->getDataLayout()) &&
"non noop cast is found during rematerialization");
Type *SrcTy = CI->getOperand(0)->getType();
Cost += TTI.getCastInstrCost(CI->getOpcode(), CI->getType(), SrcTy);
} else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Instr)) {
// Cost of the address calculation
Type *ValTy = GEP->getSourceElementType();
Cost += TTI.getAddressComputationCost(ValTy);
// And cost of the GEP itself
// TODO: Use TTI->getGEPCost here (it exists, but appears to be not
// allowed for the external usage)
if (!GEP->hasAllConstantIndices())
Cost += 2;
} else {
llvm_unreachable("unsupported instruciton type during rematerialization");
}
}
return Cost;
}
// From the statepoint live set pick values that are cheaper to recompute then
// to relocate. Remove this values from the live set, rematerialize them after
// statepoint and record them in "Info" structure. Note that similar to
// relocated values we don't do any user adjustments here.
static void rematerializeLiveValues(CallSite CS,
PartiallyConstructedSafepointRecord &Info,
TargetTransformInfo &TTI) {
const unsigned int ChainLengthThreshold = 10;
2015-05-25 09:43:23 +08:00
// Record values we are going to delete from this statepoint live set.
// We can not di this in following loop due to iterator invalidation.
SmallVector<Value *, 32> LiveValuesToBeDeleted;
for (Value *LiveValue: Info.LiveSet) {
// For each live pointer find it's defining chain
SmallVector<Instruction *, 3> ChainToBase;
assert(Info.PointerToBase.count(LiveValue));
bool FoundChain =
findRematerializableChainToBasePointer(ChainToBase,
LiveValue,
Info.PointerToBase[LiveValue]);
// Nothing to do, or chain is too long
if (!FoundChain ||
ChainToBase.size() == 0 ||
ChainToBase.size() > ChainLengthThreshold)
continue;
// Compute cost of this chain
unsigned Cost = chainToBasePointerCost(ChainToBase, TTI);
// TODO: We can also account for cases when we will be able to remove some
// of the rematerialized values by later optimization passes. I.e if
// we rematerialized several intersecting chains. Or if original values
// don't have any uses besides this statepoint.
// For invokes we need to rematerialize each chain twice - for normal and
// for unwind basic blocks. Model this by multiplying cost by two.
if (CS.isInvoke()) {
Cost *= 2;
}
// If it's too expensive - skip it
if (Cost >= RematerializationThreshold)
continue;
// Remove value from the live set
LiveValuesToBeDeleted.push_back(LiveValue);
// Clone instructions and record them inside "Info" structure
// Walk backwards to visit top-most instructions first
std::reverse(ChainToBase.begin(), ChainToBase.end());
// Utility function which clones all instructions from "ChainToBase"
// and inserts them before "InsertBefore". Returns rematerialized value
// which should be used after statepoint.
auto rematerializeChain = [&ChainToBase](Instruction *InsertBefore) {
Instruction *LastClonedValue = nullptr;
Instruction *LastValue = nullptr;
for (Instruction *Instr: ChainToBase) {
// Only GEP's and casts are suported as we need to be careful to not
// introduce any new uses of pointers not in the liveset.
// Note that it's fine to introduce new uses of pointers which were
// otherwise not used after this statepoint.
assert(isa<GetElementPtrInst>(Instr) || isa<CastInst>(Instr));
Instruction *ClonedValue = Instr->clone();
ClonedValue->insertBefore(InsertBefore);
ClonedValue->setName(Instr->getName() + ".remat");
// If it is not first instruction in the chain then it uses previously
// cloned value. We should update it to use cloned value.
if (LastClonedValue) {
assert(LastValue);
ClonedValue->replaceUsesOfWith(LastValue, LastClonedValue);
#ifndef NDEBUG
// Assert that cloned instruction does not use any instructions from
// this chain other than LastClonedValue
for (auto OpValue : ClonedValue->operand_values()) {
assert(std::find(ChainToBase.begin(), ChainToBase.end(), OpValue) ==
ChainToBase.end() &&
"incorrect use in rematerialization chain");
}
#endif
}
LastClonedValue = ClonedValue;
LastValue = Instr;
}
assert(LastClonedValue);
return LastClonedValue;
};
// Different cases for calls and invokes. For invokes we need to clone
// instructions both on normal and unwind path.
if (CS.isCall()) {
Instruction *InsertBefore = CS.getInstruction()->getNextNode();
assert(InsertBefore);
Instruction *RematerializedValue = rematerializeChain(InsertBefore);
Info.RematerializedValues[RematerializedValue] = LiveValue;
} else {
InvokeInst *Invoke = cast<InvokeInst>(CS.getInstruction());
Instruction *NormalInsertBefore =
&*Invoke->getNormalDest()->getFirstInsertionPt();
Instruction *UnwindInsertBefore =
&*Invoke->getUnwindDest()->getFirstInsertionPt();
Instruction *NormalRematerializedValue =
rematerializeChain(NormalInsertBefore);
Instruction *UnwindRematerializedValue =
rematerializeChain(UnwindInsertBefore);
Info.RematerializedValues[NormalRematerializedValue] = LiveValue;
Info.RematerializedValues[UnwindRematerializedValue] = LiveValue;
}
}
// Remove rematerializaed values from the live set
for (auto LiveValue: LiveValuesToBeDeleted) {
Info.LiveSet.erase(LiveValue);
}
}
static bool insertParsePoints(Function &F, DominatorTree &DT,
TargetTransformInfo &TTI,
SmallVectorImpl<CallSite> &ToUpdate) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#ifndef NDEBUG
// sanity check the input
std::set<CallSite> Uniqued;
Uniqued.insert(ToUpdate.begin(), ToUpdate.end());
assert(Uniqued.size() == ToUpdate.size() && "no duplicates please!");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (CallSite CS : ToUpdate) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
assert(CS.getInstruction()->getParent()->getParent() == &F);
assert((UseDeoptBundles || isStatepoint(CS)) &&
"expected to already be a deopt statepoint");
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
#endif
// When inserting gc.relocates for invokes, we need to be able to insert at
// the top of the successor blocks. See the comment on
// normalForInvokeSafepoint on exactly what is needed. Note that this step
// may restructure the CFG.
for (CallSite CS : ToUpdate) {
if (!CS.isInvoke())
continue;
auto *II = cast<InvokeInst>(CS.getInstruction());
normalizeForInvokeSafepoint(II->getNormalDest(), II->getParent(), DT);
normalizeForInvokeSafepoint(II->getUnwindDest(), II->getParent(), DT);
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// A list of dummy calls added to the IR to keep various values obviously
// live in the IR. We'll remove all of these when done.
SmallVector<CallInst *, 64> Holders;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Insert a dummy call with all of the arguments to the vm_state we'll need
// for the actual safepoint insertion. This ensures reference arguments in
// the deopt argument list are considered live through the safepoint (and
// thus makes sure they get relocated.)
for (CallSite CS : ToUpdate) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
SmallVector<Value *, 64> DeoptValues;
iterator_range<const Use *> DeoptStateRange =
UseDeoptBundles
? iterator_range<const Use *>(GetDeoptBundleOperands(CS))
: iterator_range<const Use *>(Statepoint(CS).vm_state_args());
for (Value *Arg : DeoptStateRange) {
assert(!isUnhandledGCPointerType(Arg->getType()) &&
"support for FCA unimplemented");
if (isHandledGCPointerType(Arg->getType()))
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
DeoptValues.push_back(Arg);
}
insertUseHolderAfter(CS, DeoptValues, Holders);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
SmallVector<PartiallyConstructedSafepointRecord, 64> Records(ToUpdate.size());
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// A) Identify all gc pointers which are statically live at the given call
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// site.
findLiveReferences(F, DT, ToUpdate, Records);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// B) Find the base pointers for each live pointer
/* scope for caching */ {
// Cache the 'defining value' relation used in the computation and
// insertion of base phis and selects. This ensures that we don't insert
// large numbers of duplicate base_phis.
DefiningValueMapTy DVCache;
for (size_t i = 0; i < Records.size(); i++) {
PartiallyConstructedSafepointRecord &info = Records[i];
findBasePointers(DT, DVCache, ToUpdate[i], info);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
} // end of cache scope
// The base phi insertion logic (for any safepoint) may have inserted new
// instructions which are now live at some safepoint. The simplest such
// example is:
// loop:
// phi a <-- will be a new base_phi here
// safepoint 1 <-- that needs to be live here
// gep a + 1
// safepoint 2
// br loop
// We insert some dummy calls after each safepoint to definitely hold live
// the base pointers which were identified for that safepoint. We'll then
// ask liveness for _every_ base inserted to see what is now live. Then we
// remove the dummy calls.
Holders.reserve(Holders.size() + Records.size());
for (size_t i = 0; i < Records.size(); i++) {
PartiallyConstructedSafepointRecord &Info = Records[i];
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
SmallVector<Value *, 128> Bases;
for (auto Pair : Info.PointerToBase)
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
Bases.push_back(Pair.second);
insertUseHolderAfter(ToUpdate[i], Bases, Holders);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// By selecting base pointers, we've effectively inserted new uses. Thus, we
// need to rerun liveness. We may *also* have inserted new defs, but that's
// not the key issue.
recomputeLiveInValues(F, DT, ToUpdate, Records);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
if (PrintBasePointers) {
for (auto &Info : Records) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
errs() << "Base Pairs: (w/Relocation)\n";
for (auto Pair : Info.PointerToBase) {
errs() << " derived ";
Pair.first->printAsOperand(errs(), false);
errs() << " base ";
Pair.second->printAsOperand(errs(), false);
errs() << "\n";
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
}
// It is possible that non-constant live variables have a constant base. For
// example, a GEP with a variable offset from a global. In this case we can
// remove it from the liveset. We already don't add constants to the liveset
// because we assume they won't move at runtime and the GC doesn't need to be
// informed about them. The same reasoning applies if the base is constant.
// Note that the relocation placement code relies on this filtering for
// correctness as it expects the base to be in the liveset, which isn't true
// if the base is constant.
for (auto &Info : Records)
for (auto &BasePair : Info.PointerToBase)
if (isa<Constant>(BasePair.second))
Info.LiveSet.erase(BasePair.first);
for (CallInst *CI : Holders)
CI->eraseFromParent();
Holders.clear();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Do a limited scalarization of any live at safepoint vector values which
// contain pointers. This enables this pass to run after vectorization at
// the cost of some possible performance loss. Note: This is known to not
// handle updating of the side tables correctly which can lead to relocation
// bugs when the same vector is live at multiple statepoints. We're in the
// process of implementing the alternate lowering - relocating the
// vector-of-pointers as first class item and updating the backend to
// understand that - but that's not yet complete.
if (UseVectorSplit)
for (size_t i = 0; i < Records.size(); i++) {
PartiallyConstructedSafepointRecord &Info = Records[i];
Instruction *Statepoint = ToUpdate[i].getInstruction();
splitVectorValues(cast<Instruction>(Statepoint), Info.LiveSet,
Info.PointerToBase, DT);
}
// In order to reduce live set of statepoint we might choose to rematerialize
// some values instead of relocating them. This is purely an optimization and
// does not influence correctness.
for (size_t i = 0; i < Records.size(); i++)
rematerializeLiveValues(ToUpdate[i], Records[i], TTI);
// We need this to safely RAUW and delete call or invoke return values that
// may themselves be live over a statepoint. For details, please see usage in
// makeStatepointExplicitImpl.
std::vector<DeferredReplacement> Replacements;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Now run through and replace the existing statepoints with new ones with
// the live variables listed. We do not yet update uses of the values being
// relocated. We have references to live variables that need to
// survive to the last iteration of this loop. (By construction, the
// previous statepoint can not be a live variable, thus we can and remove
// the old statepoint calls as we go.)
for (size_t i = 0; i < Records.size(); i++)
makeStatepointExplicit(DT, ToUpdate[i], Records[i], Replacements);
ToUpdate.clear(); // prevent accident use of invalid CallSites
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
for (auto &PR : Replacements)
PR.doReplacement();
Replacements.clear();
for (auto &Info : Records) {
// These live sets may contain state Value pointers, since we replaced calls
// with operand bundles with calls wrapped in gc.statepoint, and some of
// those calls may have been def'ing live gc pointers. Clear these out to
// avoid accidentally using them.
//
// TODO: We should create a separate data structure that does not contain
// these live sets, and migrate to using that data structure from this point
// onward.
Info.LiveSet.clear();
Info.PointerToBase.clear();
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Do all the fixups of the original live variables to their relocated selves
SmallVector<Value *, 128> Live;
for (size_t i = 0; i < Records.size(); i++) {
PartiallyConstructedSafepointRecord &Info = Records[i];
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// We can't simply save the live set from the original insertion. One of
// the live values might be the result of a call which needs a safepoint.
// That Value* no longer exists and we need to use the new gc_result.
// Thankfully, the live set is embedded in the statepoint (and updated), so
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// we just grab that.
Statepoint Statepoint(Info.StatepointToken);
Live.insert(Live.end(), Statepoint.gc_args_begin(),
Statepoint.gc_args_end());
#ifndef NDEBUG
// Do some basic sanity checks on our liveness results before performing
// relocation. Relocation can and will turn mistakes in liveness results
// into non-sensical code which is must harder to debug.
// TODO: It would be nice to test consistency as well
assert(DT.isReachableFromEntry(Info.StatepointToken->getParent()) &&
"statepoint must be reachable or liveness is meaningless");
for (Value *V : Statepoint.gc_args()) {
if (!isa<Instruction>(V))
// Non-instruction values trivial dominate all possible uses
continue;
auto *LiveInst = cast<Instruction>(V);
assert(DT.isReachableFromEntry(LiveInst->getParent()) &&
"unreachable values should never be live");
assert(DT.dominates(LiveInst, Info.StatepointToken) &&
"basic SSA liveness expectation violated by liveness analysis");
}
#endif
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
unique_unsorted(Live);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
#ifndef NDEBUG
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// sanity check
for (auto *Ptr : Live)
[rs4gc] Optionally directly relocated vector of pointers This patch teaches rewrite-statepoints-for-gc to relocate vector-of-pointers directly rather than trying to split them. This builds on the recent lowering/IR changes to allow vector typed gc.relocates. The motivation for this is that we recently found a bug in the vector splitting code where depending on visit order, a vector might not be relocated at some safepoint. Specifically, the bug is that the splitting code wasn't updating the side tables (live vector) of other safepoints. As a result, a vector which was live at two safepoints might not be updated at one of them. However, if you happened to visit safepoints in post order over the dominator tree, everything worked correctly. Weirdly, it turns out that post order is actually an incredibly common order to visit instructions in in practice. Frustratingly, I have not managed to write a test case which actually hits this. I can only reproduce it in large IR files produced by actual applications. Rather than continue to make this code more complicated, we can remove all of the complexity by just representing the relocation of the entire vector natively in the IR. At the moment, the new functionality is hidden behind a flag. To use this code, you need to pass "-rs4gc-split-vector-values=0". Once I have a chance to stress test with this option and get feedback from other users, my plan is to flip the default and remove the original splitting code. I would just remove it now, but given the rareness of the bug, I figured it was better to leave it in place until the new approach has been stress tested. Differential Revision: http://reviews.llvm.org/D15982 llvm-svn: 257244
2016-01-09 09:31:13 +08:00
assert(isHandledGCPointerType(Ptr->getType()) &&
"must be a gc pointer type");
#endif
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
relocationViaAlloca(F, DT, Live, Records);
return !Records.empty();
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// Handles both return values and arguments for Functions and CallSites.
template <typename AttrHolder>
static void RemoveNonValidAttrAtIndex(LLVMContext &Ctx, AttrHolder &AH,
unsigned Index) {
AttrBuilder R;
if (AH.getDereferenceableBytes(Index))
R.addAttribute(Attribute::get(Ctx, Attribute::Dereferenceable,
AH.getDereferenceableBytes(Index)));
if (AH.getDereferenceableOrNullBytes(Index))
R.addAttribute(Attribute::get(Ctx, Attribute::DereferenceableOrNull,
AH.getDereferenceableOrNullBytes(Index)));
if (AH.doesNotAlias(Index))
R.addAttribute(Attribute::NoAlias);
if (!R.empty())
AH.setAttributes(AH.getAttributes().removeAttributes(
Ctx, Index, AttributeSet::get(Ctx, Index, R)));
}
void
RewriteStatepointsForGC::stripNonValidAttributesFromPrototype(Function &F) {
LLVMContext &Ctx = F.getContext();
for (Argument &A : F.args())
if (isa<PointerType>(A.getType()))
RemoveNonValidAttrAtIndex(Ctx, F, A.getArgNo() + 1);
if (isa<PointerType>(F.getReturnType()))
RemoveNonValidAttrAtIndex(Ctx, F, AttributeSet::ReturnIndex);
}
void RewriteStatepointsForGC::stripNonValidAttributesFromBody(Function &F) {
if (F.empty())
return;
LLVMContext &Ctx = F.getContext();
MDBuilder Builder(Ctx);
for (Instruction &I : instructions(F)) {
if (const MDNode *MD = I.getMetadata(LLVMContext::MD_tbaa)) {
assert(MD->getNumOperands() < 5 && "unrecognized metadata shape!");
bool IsImmutableTBAA =
MD->getNumOperands() == 4 &&
mdconst::extract<ConstantInt>(MD->getOperand(3))->getValue() == 1;
if (!IsImmutableTBAA)
continue; // no work to do, MD_tbaa is already marked mutable
MDNode *Base = cast<MDNode>(MD->getOperand(0));
MDNode *Access = cast<MDNode>(MD->getOperand(1));
uint64_t Offset =
mdconst::extract<ConstantInt>(MD->getOperand(2))->getZExtValue();
MDNode *MutableTBAA =
Builder.createTBAAStructTagNode(Base, Access, Offset);
I.setMetadata(LLVMContext::MD_tbaa, MutableTBAA);
}
if (CallSite CS = CallSite(&I)) {
for (int i = 0, e = CS.arg_size(); i != e; i++)
if (isa<PointerType>(CS.getArgument(i)->getType()))
RemoveNonValidAttrAtIndex(Ctx, CS, i + 1);
if (isa<PointerType>(CS.getType()))
RemoveNonValidAttrAtIndex(Ctx, CS, AttributeSet::ReturnIndex);
}
}
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
/// Returns true if this function should be rewritten by this pass. The main
/// point of this function is as an extension point for custom logic.
static bool shouldRewriteStatepointsIn(Function &F) {
// TODO: This should check the GCStrategy
if (F.hasGC()) {
const auto &FunctionGCName = F.getGC();
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const StringRef StatepointExampleName("statepoint-example");
const StringRef CoreCLRName("coreclr");
return (StatepointExampleName == FunctionGCName) ||
2015-05-25 09:43:34 +08:00
(CoreCLRName == FunctionGCName);
} else
return false;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
void RewriteStatepointsForGC::stripNonValidAttributes(Module &M) {
#ifndef NDEBUG
assert(std::any_of(M.begin(), M.end(), shouldRewriteStatepointsIn) &&
"precondition!");
#endif
for (Function &F : M)
stripNonValidAttributesFromPrototype(F);
for (Function &F : M)
stripNonValidAttributesFromBody(F);
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
bool RewriteStatepointsForGC::runOnFunction(Function &F) {
// Nothing to do for declarations.
if (F.isDeclaration() || F.empty())
return false;
// Policy choice says not to rewrite - the most common reason is that we're
// compiling code without a GCStrategy.
if (!shouldRewriteStatepointsIn(F))
return false;
DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>(F).getDomTree();
TargetTransformInfo &TTI =
getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
auto NeedsRewrite = [](Instruction &I) {
if (UseDeoptBundles) {
if (ImmutableCallSite CS = ImmutableCallSite(&I))
return !callsGCLeafFunction(CS);
return false;
}
return isStatepoint(I);
};
// Gather all the statepoints which need rewritten. Be careful to only
// consider those in reachable code since we need to ask dominance queries
// when rewriting. We'll delete the unreachable ones in a moment.
SmallVector<CallSite, 64> ParsePointNeeded;
bool HasUnreachableStatepoint = false;
for (Instruction &I : instructions(F)) {
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// TODO: only the ones with the flag set!
if (NeedsRewrite(I)) {
if (DT.isReachableFromEntry(I.getParent()))
ParsePointNeeded.push_back(CallSite(&I));
else
HasUnreachableStatepoint = true;
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
bool MadeChange = false;
// Delete any unreachable statepoints so that we don't have unrewritten
// statepoints surviving this pass. This makes testing easier and the
// resulting IR less confusing to human readers. Rather than be fancy, we
// just reuse a utility function which removes the unreachable blocks.
if (HasUnreachableStatepoint)
MadeChange |= removeUnreachableBlocks(F);
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
// Return early if no work to do.
if (ParsePointNeeded.empty())
return MadeChange;
// As a prepass, go ahead and aggressively destroy single entry phi nodes.
// These are created by LCSSA. They have the effect of increasing the size
// of liveness sets for no good reason. It may be harder to do this post
// insertion since relocations and base phis can confuse things.
for (BasicBlock &BB : F)
if (BB.getUniquePredecessor()) {
MadeChange = true;
FoldSingleEntryPHINodes(&BB);
}
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
[RewriteStatepointsForGC] Avoid using unrelocated pointers after safepoints To be clear: this is an *optimization* not a correctness change. CodeGenPrep likes to duplicate icmps feeding branch instructions to take advantage of x86's ability to fuze many comparison/branch patterns into a single micro-op and to reduce the need for materializing i1s into general registers. PlaceSafepoints likes to place safepoint polls right at the end of basic blocks (immediately before terminators) when inserting entry and backedge safepoints. These two heuristics interact in a somewhat unfortunate way where the branch terminating the original block will be controlled by a condition driven by unrelocated pointers. This forces the register allocator to keep both the relocated and unrelocated values of the pointers feeding the icmp alive over the safepoint poll. One simple fix would have been to just adjust PlaceSafepoints to move one back in the basic block, but you can reach similar cases as a result of LICM or other hoisting passes. As a result, doing a post insertion fixup seems to be more robust. I considered doing this in CodeGenPrep itself, but having to update the live sets of already rewritten safepoints gets complicated fast. In particular, you can't just use def/use information because by moving the icmp, we're extending the live range of it's inputs potentially. Instead, this patch teaches RewriteStatepointsForGC to make the required adjustments before making the relocations explicit in the IR. This change really highlights the fact that RSForGC is a CodeGenPrep-like pass which is performing target specific lowering. In the long run, we may even want to combine the two though this would require a lot more smarts to be integrated into RSForGC first. We currently rely on being able to run a set of cleanup passes post rewriting because the IR RSForGC generates is pretty damn ugly. Differential Revision: http://reviews.llvm.org/D11819 llvm-svn: 244821
2015-08-13 06:11:45 +08:00
// Before we start introducing relocations, we want to tweak the IR a bit to
// avoid unfortunate code generation effects. The main example is that we
// want to try to make sure the comparison feeding a branch is after any
// safepoints. Otherwise, we end up with a comparison of pre-relocation
// values feeding a branch after relocation. This is semantically correct,
// but results in extra register pressure since both the pre-relocation and
// post-relocation copies must be available in registers. For code without
// relocations this is handled elsewhere, but teaching the scheduler to
// reverse the transform we're about to do would be slightly complex.
// Note: This may extend the live range of the inputs to the icmp and thus
// increase the liveset of any statepoint we move over. This is profitable
// as long as all statepoints are in rare blocks. If we had in-register
// lowering for live values this would be a much safer transform.
auto getConditionInst = [](TerminatorInst *TI) -> Instruction* {
if (auto *BI = dyn_cast<BranchInst>(TI))
if (BI->isConditional())
return dyn_cast<Instruction>(BI->getCondition());
// TODO: Extend this to handle switches
return nullptr;
};
for (BasicBlock &BB : F) {
TerminatorInst *TI = BB.getTerminator();
if (auto *Cond = getConditionInst(TI))
// TODO: Handle more than just ICmps here. We should be able to move
// most instructions without side effects or memory access.
if (isa<ICmpInst>(Cond) && Cond->hasOneUse()) {
MadeChange = true;
Cond->moveBefore(TI);
}
}
MadeChange |= insertParsePoints(F, DT, TTI, ParsePointNeeded);
return MadeChange;
Add a pass for constructing gc.statepoint sequences w/explicit relocations This patch consists of a single pass whose only purpose is to visit previous inserted gc.statepoints which do not have gc.relocates inserted yet, and insert them. This can be used either immediately after IR generation to perform 'early safepoint insertion' or late in the pass order to perform 'late insertion'. This patch is setting the stage for work to continue in tree. In particular, there are known naming and style violations in the current patch. I'll try to get those resolved over the next week or so. As I touch each area to make style changes, I need to make sure we have adequate testing in place. As part of the cleanup, I will be cleaning up a collection of test cases we have out of tree and submitting them upstream. The tests included in this change are very basic and mostly to provide examples of usage. The pass has several main subproblems it needs to address: - First, it has identify any live pointers. In the current code, the use of address spaces to distinguish pointers to GC managed objects is hard coded, but this will become parametrizable in the near future. Note that the current change doesn't actually contain a useful liveness analysis. It was seperated into a followup change as the code wasn't ready to be shared. Instead, the current implementation just considers any dominating def of appropriate pointer type to be live. - Second, it has to identify base pointers for each live pointer. This is a fairly straight forward data flow algorithm. - Third, the information in the previous steps is used to actually introduce rewrites. Rather than trying to do this by hand, we simply re-purpose the code behind Mem2Reg to do this for us. llvm-svn: 229945
2015-02-20 09:06:44 +08:00
}
// liveness computation via standard dataflow
// -------------------------------------------------------------------
// TODO: Consider using bitvectors for liveness, the set of potentially
// interesting values should be small and easy to pre-compute.
/// Compute the live-in set for the location rbegin starting from
/// the live-out set of the basic block
static void computeLiveInValues(BasicBlock::reverse_iterator rbegin,
BasicBlock::reverse_iterator rend,
DenseSet<Value *> &LiveTmp) {
for (BasicBlock::reverse_iterator ritr = rbegin; ritr != rend; ritr++) {
Instruction *I = &*ritr;
// KILL/Def - Remove this definition from LiveIn
LiveTmp.erase(I);
// Don't consider *uses* in PHI nodes, we handle their contribution to
// predecessor blocks when we seed the LiveOut sets
if (isa<PHINode>(I))
continue;
// USE - Add to the LiveIn set for this instruction
for (Value *V : I->operands()) {
assert(!isUnhandledGCPointerType(V->getType()) &&
"support for FCA unimplemented");
if (isHandledGCPointerType(V->getType()) && !isa<Constant>(V)) {
// The choice to exclude all things constant here is slightly subtle.
// There are two independent reasons:
// - We assume that things which are constant (from LLVM's definition)
// do not move at runtime. For example, the address of a global
// variable is fixed, even though it's contents may not be.
// - Second, we can't disallow arbitrary inttoptr constants even
// if the language frontend does. Optimization passes are free to
// locally exploit facts without respect to global reachability. This
// can create sections of code which are dynamically unreachable and
// contain just about anything. (see constants.ll in tests)
LiveTmp.insert(V);
}
}
}
}
static void computeLiveOutSeed(BasicBlock *BB, DenseSet<Value *> &LiveTmp) {
for (BasicBlock *Succ : successors(BB)) {
const BasicBlock::iterator E(Succ->getFirstNonPHI());
for (BasicBlock::iterator I = Succ->begin(); I != E; I++) {
PHINode *Phi = cast<PHINode>(&*I);
Value *V = Phi->getIncomingValueForBlock(BB);
assert(!isUnhandledGCPointerType(V->getType()) &&
"support for FCA unimplemented");
if (isHandledGCPointerType(V->getType()) && !isa<Constant>(V)) {
LiveTmp.insert(V);
}
}
}
}
static DenseSet<Value *> computeKillSet(BasicBlock *BB) {
DenseSet<Value *> KillSet;
for (Instruction &I : *BB)
if (isHandledGCPointerType(I.getType()))
KillSet.insert(&I);
return KillSet;
}
#ifndef NDEBUG
/// Check that the items in 'Live' dominate 'TI'. This is used as a basic
/// sanity check for the liveness computation.
static void checkBasicSSA(DominatorTree &DT, DenseSet<Value *> &Live,
TerminatorInst *TI, bool TermOkay = false) {
for (Value *V : Live) {
if (auto *I = dyn_cast<Instruction>(V)) {
// The terminator can be a member of the LiveOut set. LLVM's definition
// of instruction dominance states that V does not dominate itself. As
// such, we need to special case this to allow it.
if (TermOkay && TI == I)
continue;
assert(DT.dominates(I, TI) &&
"basic SSA liveness expectation violated by liveness analysis");
}
}
}
/// Check that all the liveness sets used during the computation of liveness
/// obey basic SSA properties. This is useful for finding cases where we miss
/// a def.
static void checkBasicSSA(DominatorTree &DT, GCPtrLivenessData &Data,
BasicBlock &BB) {
checkBasicSSA(DT, Data.LiveSet[&BB], BB.getTerminator());
checkBasicSSA(DT, Data.LiveOut[&BB], BB.getTerminator(), true);
checkBasicSSA(DT, Data.LiveIn[&BB], BB.getTerminator());
}
#endif
static void computeLiveInValues(DominatorTree &DT, Function &F,
GCPtrLivenessData &Data) {
SmallSetVector<BasicBlock *, 200> Worklist;
auto AddPredsToWorklist = [&](BasicBlock *BB) {
// We use a SetVector so that we don't have duplicates in the worklist.
Worklist.insert(pred_begin(BB), pred_end(BB));
};
auto NextItem = [&]() {
BasicBlock *BB = Worklist.back();
Worklist.pop_back();
return BB;
};
// Seed the liveness for each individual block
for (BasicBlock &BB : F) {
Data.KillSet[&BB] = computeKillSet(&BB);
Data.LiveSet[&BB].clear();
computeLiveInValues(BB.rbegin(), BB.rend(), Data.LiveSet[&BB]);
#ifndef NDEBUG
for (Value *Kill : Data.KillSet[&BB])
assert(!Data.LiveSet[&BB].count(Kill) && "live set contains kill");
#endif
Data.LiveOut[&BB] = DenseSet<Value *>();
computeLiveOutSeed(&BB, Data.LiveOut[&BB]);
Data.LiveIn[&BB] = Data.LiveSet[&BB];
set_union(Data.LiveIn[&BB], Data.LiveOut[&BB]);
set_subtract(Data.LiveIn[&BB], Data.KillSet[&BB]);
if (!Data.LiveIn[&BB].empty())
AddPredsToWorklist(&BB);
}
// Propagate that liveness until stable
while (!Worklist.empty()) {
BasicBlock *BB = NextItem();
// Compute our new liveout set, then exit early if it hasn't changed
// despite the contribution of our successor.
DenseSet<Value *> LiveOut = Data.LiveOut[BB];
const auto OldLiveOutSize = LiveOut.size();
for (BasicBlock *Succ : successors(BB)) {
assert(Data.LiveIn.count(Succ));
set_union(LiveOut, Data.LiveIn[Succ]);
}
// assert OutLiveOut is a subset of LiveOut
if (OldLiveOutSize == LiveOut.size()) {
// If the sets are the same size, then we didn't actually add anything
// when unioning our successors LiveIn Thus, the LiveIn of this block
// hasn't changed.
continue;
}
Data.LiveOut[BB] = LiveOut;
// Apply the effects of this basic block
DenseSet<Value *> LiveTmp = LiveOut;
set_union(LiveTmp, Data.LiveSet[BB]);
set_subtract(LiveTmp, Data.KillSet[BB]);
assert(Data.LiveIn.count(BB));
const DenseSet<Value *> &OldLiveIn = Data.LiveIn[BB];
// assert: OldLiveIn is a subset of LiveTmp
if (OldLiveIn.size() != LiveTmp.size()) {
Data.LiveIn[BB] = LiveTmp;
AddPredsToWorklist(BB);
}
} // while( !worklist.empty() )
#ifndef NDEBUG
// Sanity check our output against SSA properties. This helps catch any
// missing kills during the above iteration.
for (BasicBlock &BB : F) {
checkBasicSSA(DT, Data, BB);
}
#endif
}
static void findLiveSetAtInst(Instruction *Inst, GCPtrLivenessData &Data,
StatepointLiveSetTy &Out) {
BasicBlock *BB = Inst->getParent();
// Note: The copy is intentional and required
assert(Data.LiveOut.count(BB));
DenseSet<Value *> LiveOut = Data.LiveOut[BB];
// We want to handle the statepoint itself oddly. It's
// call result is not live (normal), nor are it's arguments
// (unless they're used again later). This adjustment is
// specifically what we need to relocate
BasicBlock::reverse_iterator rend(Inst->getIterator());
computeLiveInValues(BB->rbegin(), rend, LiveOut);
LiveOut.erase(Inst);
Out.insert(LiveOut.begin(), LiveOut.end());
}
static void recomputeLiveInValues(GCPtrLivenessData &RevisedLivenessData,
const CallSite &CS,
PartiallyConstructedSafepointRecord &Info) {
Instruction *Inst = CS.getInstruction();
StatepointLiveSetTy Updated;
findLiveSetAtInst(Inst, RevisedLivenessData, Updated);
#ifndef NDEBUG
DenseSet<Value *> Bases;
for (auto KVPair : Info.PointerToBase) {
Bases.insert(KVPair.second);
}
#endif
// We may have base pointers which are now live that weren't before. We need
// to update the PointerToBase structure to reflect this.
for (auto V : Updated)
if (!Info.PointerToBase.count(V)) {
assert(Bases.count(V) && "can't find base for unexpected live value");
Info.PointerToBase[V] = V;
continue;
}
#ifndef NDEBUG
for (auto V : Updated) {
assert(Info.PointerToBase.count(V) &&
"must be able to find base for live value");
}
#endif
// Remove any stale base mappings - this can happen since our liveness is
// more precise then the one inherent in the base pointer analysis
DenseSet<Value *> ToErase;
for (auto KVPair : Info.PointerToBase)
if (!Updated.count(KVPair.first))
ToErase.insert(KVPair.first);
for (auto V : ToErase)
Info.PointerToBase.erase(V);
#ifndef NDEBUG
for (auto KVPair : Info.PointerToBase)
assert(Updated.count(KVPair.first) && "record for non-live value");
#endif
Info.LiveSet = Updated;
}