llvm-project/llvm/lib/Analysis/TargetTransformInfo.cpp

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//===- llvm/Analysis/TargetTransformInfo.cpp ------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/TargetTransformInfo.h"
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
#include "llvm/Analysis/TargetTransformInfoImpl.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include <utility>
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "tti"
static cl::opt<bool> EnableReduxCost("costmodel-reduxcost", cl::init(false),
cl::Hidden,
cl::desc("Recognize reduction patterns."));
namespace {
/// No-op implementation of the TTI interface using the utility base
/// classes.
///
/// This is used when no target specific information is available.
struct NoTTIImpl : TargetTransformInfoImplCRTPBase<NoTTIImpl> {
explicit NoTTIImpl(const DataLayout &DL)
: TargetTransformInfoImplCRTPBase<NoTTIImpl>(DL) {}
};
}
TargetTransformInfo::TargetTransformInfo(const DataLayout &DL)
: TTIImpl(new Model<NoTTIImpl>(NoTTIImpl(DL))) {}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
TargetTransformInfo::~TargetTransformInfo() {}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
TargetTransformInfo::TargetTransformInfo(TargetTransformInfo &&Arg)
: TTIImpl(std::move(Arg.TTIImpl)) {}
Switch TargetTransformInfo from an immutable analysis pass that requires a TargetMachine to construct (and thus isn't always available), to an analysis group that supports layered implementations much like AliasAnalysis does. This is a pretty massive change, with a few parts that I was unable to easily separate (sorry), so I'll walk through it. The first step of this conversion was to make TargetTransformInfo an analysis group, and to sink the nonce implementations in ScalarTargetTransformInfo and VectorTargetTranformInfo into a NoTargetTransformInfo pass. This allows other passes to add a hard requirement on TTI, and assume they will always get at least on implementation. The TargetTransformInfo analysis group leverages the delegation chaining trick that AliasAnalysis uses, where the base class for the analysis group delegates to the previous analysis *pass*, allowing all but tho NoFoo analysis passes to only implement the parts of the interfaces they support. It also introduces a new trick where each pass in the group retains a pointer to the top-most pass that has been initialized. This allows passes to implement one API in terms of another API and benefit when some other pass above them in the stack has more precise results for the second API. The second step of this conversion is to create a pass that implements the TargetTransformInfo analysis using the target-independent abstractions in the code generator. This replaces the ScalarTargetTransformImpl and VectorTargetTransformImpl classes in lib/Target with a single pass in lib/CodeGen called BasicTargetTransformInfo. This class actually provides most of the TTI functionality, basing it upon the TargetLowering abstraction and other information in the target independent code generator. The third step of the conversion adds support to all TargetMachines to register custom analysis passes. This allows building those passes with access to TargetLowering or other target-specific classes, and it also allows each target to customize the set of analysis passes desired in the pass manager. The baseline LLVMTargetMachine implements this interface to add the BasicTTI pass to the pass manager, and all of the tools that want to support target-aware TTI passes call this routine on whatever target machine they end up with to add the appropriate passes. The fourth step of the conversion created target-specific TTI analysis passes for the X86 and ARM backends. These passes contain the custom logic that was previously in their extensions of the ScalarTargetTransformInfo and VectorTargetTransformInfo interfaces. I separated them into their own file, as now all of the interface bits are private and they just expose a function to create the pass itself. Then I extended these target machines to set up a custom set of analysis passes, first adding BasicTTI as a fallback, and then adding their customized TTI implementations. The fourth step required logic that was shared between the target independent layer and the specific targets to move to a different interface, as they no longer derive from each other. As a consequence, a helper functions were added to TargetLowering representing the common logic needed both in the target implementation and the codegen implementation of the TTI pass. While technically this is the only change that could have been committed separately, it would have been a nightmare to extract. The final step of the conversion was just to delete all the old boilerplate. This got rid of the ScalarTargetTransformInfo and VectorTargetTransformInfo classes, all of the support in all of the targets for producing instances of them, and all of the support in the tools for manually constructing a pass based around them. Now that TTI is a relatively normal analysis group, two things become straightforward. First, we can sink it into lib/Analysis which is a more natural layer for it to live. Second, clients of this interface can depend on it *always* being available which will simplify their code and behavior. These (and other) simplifications will follow in subsequent commits, this one is clearly big enough. Finally, I'm very aware that much of the comments and documentation needs to be updated. As soon as I had this working, and plausibly well commented, I wanted to get it committed and in front of the build bots. I'll be doing a few passes over documentation later if it sticks. Commits to update DragonEgg and Clang will be made presently. llvm-svn: 171681
2013-01-07 09:37:14 +08:00
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
TargetTransformInfo &TargetTransformInfo::operator=(TargetTransformInfo &&RHS) {
TTIImpl = std::move(RHS.TTIImpl);
return *this;
}
int TargetTransformInfo::getOperationCost(unsigned Opcode, Type *Ty,
Type *OpTy) const {
int Cost = TTIImpl->getOperationCost(Opcode, Ty, OpTy);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCallCost(FunctionType *FTy, int NumArgs) const {
int Cost = TTIImpl->getCallCost(FTy, NumArgs);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCallCost(const Function *F,
ArrayRef<const Value *> Arguments) const {
int Cost = TTIImpl->getCallCost(F, Arguments);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned TargetTransformInfo::getInliningThresholdMultiplier() const {
return TTIImpl->getInliningThresholdMultiplier();
}
int TargetTransformInfo::getGEPCost(Type *PointeeType, const Value *Ptr,
ArrayRef<const Value *> Operands) const {
return TTIImpl->getGEPCost(PointeeType, Ptr, Operands);
}
int TargetTransformInfo::getExtCost(const Instruction *I,
const Value *Src) const {
return TTIImpl->getExtCost(I, Src);
}
int TargetTransformInfo::getIntrinsicCost(
Intrinsic::ID IID, Type *RetTy, ArrayRef<const Value *> Arguments) const {
int Cost = TTIImpl->getIntrinsicCost(IID, RetTy, Arguments);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
[InlineCost] Improve the cost heuristic for Switch Summary: The motivation example is like below which has 13 cases but only 2 distinct targets ``` lor.lhs.false2: ; preds = %if.then switch i32 %Status, label %if.then27 [ i32 -7012, label %if.end35 i32 -10008, label %if.end35 i32 -10016, label %if.end35 i32 15000, label %if.end35 i32 14013, label %if.end35 i32 10114, label %if.end35 i32 10107, label %if.end35 i32 10105, label %if.end35 i32 10013, label %if.end35 i32 10011, label %if.end35 i32 7008, label %if.end35 i32 7007, label %if.end35 i32 5002, label %if.end35 ] ``` which is compiled into a balanced binary tree like this on AArch64 (similar on X86) ``` .LBB853_9: // %lor.lhs.false2 mov w8, #10012 cmp w19, w8 b.gt .LBB853_14 // BB#10: // %lor.lhs.false2 mov w8, #5001 cmp w19, w8 b.gt .LBB853_18 // BB#11: // %lor.lhs.false2 mov w8, #-10016 cmp w19, w8 b.eq .LBB853_23 // BB#12: // %lor.lhs.false2 mov w8, #-10008 cmp w19, w8 b.eq .LBB853_23 // BB#13: // %lor.lhs.false2 mov w8, #-7012 cmp w19, w8 b.eq .LBB853_23 b .LBB853_3 .LBB853_14: // %lor.lhs.false2 mov w8, #14012 cmp w19, w8 b.gt .LBB853_21 // BB#15: // %lor.lhs.false2 mov w8, #-10105 add w8, w19, w8 cmp w8, #9 // =9 b.hi .LBB853_17 // BB#16: // %lor.lhs.false2 orr w9, wzr, #0x1 lsl w8, w9, w8 mov w9, #517 and w8, w8, w9 cbnz w8, .LBB853_23 .LBB853_17: // %lor.lhs.false2 mov w8, #10013 cmp w19, w8 b.eq .LBB853_23 b .LBB853_3 .LBB853_18: // %lor.lhs.false2 mov w8, #-7007 add w8, w19, w8 cmp w8, #2 // =2 b.lo .LBB853_23 // BB#19: // %lor.lhs.false2 mov w8, #5002 cmp w19, w8 b.eq .LBB853_23 // BB#20: // %lor.lhs.false2 mov w8, #10011 cmp w19, w8 b.eq .LBB853_23 b .LBB853_3 .LBB853_21: // %lor.lhs.false2 mov w8, #14013 cmp w19, w8 b.eq .LBB853_23 // BB#22: // %lor.lhs.false2 mov w8, #15000 cmp w19, w8 b.ne .LBB853_3 ``` However, the inline cost model estimates the cost to be linear with the number of distinct targets and the cost of the above switch is just 2 InstrCosts. The function containing this switch is then inlined about 900 times. This change use the general way of switch lowering for the inline heuristic. It etimate the number of case clusters with the suitability check for a jump table or bit test. Considering the binary search tree built for the clusters, this change modifies the model to be linear with the size of the balanced binary tree. The model is off by default for now : -inline-generic-switch-cost=false This change was originally proposed by Haicheng in D29870. Reviewers: hans, bmakam, chandlerc, eraman, haicheng, mcrosier Reviewed By: hans Subscribers: joerg, aemerson, llvm-commits, rengolin Differential Revision: https://reviews.llvm.org/D31085 llvm-svn: 301649
2017-04-29 00:04:03 +08:00
unsigned
TargetTransformInfo::getEstimatedNumberOfCaseClusters(const SwitchInst &SI,
unsigned &JTSize) const {
return TTIImpl->getEstimatedNumberOfCaseClusters(SI, JTSize);
}
int TargetTransformInfo::getUserCost(const User *U,
ArrayRef<const Value *> Operands) const {
int Cost = TTIImpl->getUserCost(U, Operands);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
bool TargetTransformInfo::hasBranchDivergence() const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->hasBranchDivergence();
}
bool TargetTransformInfo::isSourceOfDivergence(const Value *V) const {
return TTIImpl->isSourceOfDivergence(V);
}
bool llvm::TargetTransformInfo::isAlwaysUniform(const Value *V) const {
return TTIImpl->isAlwaysUniform(V);
}
unsigned TargetTransformInfo::getFlatAddressSpace() const {
return TTIImpl->getFlatAddressSpace();
}
bool TargetTransformInfo::isLoweredToCall(const Function *F) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->isLoweredToCall(F);
}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
void TargetTransformInfo::getUnrollingPreferences(
Loop *L, ScalarEvolution &SE, UnrollingPreferences &UP) const {
return TTIImpl->getUnrollingPreferences(L, SE, UP);
}
bool TargetTransformInfo::isLegalAddImmediate(int64_t Imm) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->isLegalAddImmediate(Imm);
}
bool TargetTransformInfo::isLegalICmpImmediate(int64_t Imm) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->isLegalICmpImmediate(Imm);
}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
bool TargetTransformInfo::isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset,
bool HasBaseReg,
int64_t Scale,
unsigned AddrSpace,
Instruction *I) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->isLegalAddressingMode(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale, AddrSpace, I);
}
bool TargetTransformInfo::isLSRCostLess(LSRCost &C1, LSRCost &C2) const {
return TTIImpl->isLSRCostLess(C1, C2);
}
bool TargetTransformInfo::canMacroFuseCmp() const {
return TTIImpl->canMacroFuseCmp();
}
bool TargetTransformInfo::shouldFavorPostInc() const {
return TTIImpl->shouldFavorPostInc();
}
bool TargetTransformInfo::isLegalMaskedStore(Type *DataType) const {
return TTIImpl->isLegalMaskedStore(DataType);
}
bool TargetTransformInfo::isLegalMaskedLoad(Type *DataType) const {
return TTIImpl->isLegalMaskedLoad(DataType);
}
bool TargetTransformInfo::isLegalMaskedGather(Type *DataType) const {
return TTIImpl->isLegalMaskedGather(DataType);
}
bool TargetTransformInfo::isLegalMaskedScatter(Type *DataType) const {
return TTIImpl->isLegalMaskedScatter(DataType);
}
bool TargetTransformInfo::hasDivRemOp(Type *DataType, bool IsSigned) const {
return TTIImpl->hasDivRemOp(DataType, IsSigned);
}
bool TargetTransformInfo::hasVolatileVariant(Instruction *I,
unsigned AddrSpace) const {
return TTIImpl->hasVolatileVariant(I, AddrSpace);
}
bool TargetTransformInfo::prefersVectorizedAddressing() const {
return TTIImpl->prefersVectorizedAddressing();
}
int TargetTransformInfo::getScalingFactorCost(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset,
bool HasBaseReg,
int64_t Scale,
unsigned AddrSpace) const {
int Cost = TTIImpl->getScalingFactorCost(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale, AddrSpace);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
bool TargetTransformInfo::LSRWithInstrQueries() const {
return TTIImpl->LSRWithInstrQueries();
}
bool TargetTransformInfo::isTruncateFree(Type *Ty1, Type *Ty2) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->isTruncateFree(Ty1, Ty2);
}
bool TargetTransformInfo::isProfitableToHoist(Instruction *I) const {
return TTIImpl->isProfitableToHoist(I);
}
bool TargetTransformInfo::useAA() const { return TTIImpl->useAA(); }
bool TargetTransformInfo::isTypeLegal(Type *Ty) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->isTypeLegal(Ty);
}
unsigned TargetTransformInfo::getJumpBufAlignment() const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getJumpBufAlignment();
}
unsigned TargetTransformInfo::getJumpBufSize() const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getJumpBufSize();
}
bool TargetTransformInfo::shouldBuildLookupTables() const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->shouldBuildLookupTables();
}
bool TargetTransformInfo::shouldBuildLookupTablesForConstant(Constant *C) const {
return TTIImpl->shouldBuildLookupTablesForConstant(C);
}
bool TargetTransformInfo::useColdCCForColdCall(Function &F) const {
return TTIImpl->useColdCCForColdCall(F);
}
unsigned TargetTransformInfo::
getScalarizationOverhead(Type *Ty, bool Insert, bool Extract) const {
return TTIImpl->getScalarizationOverhead(Ty, Insert, Extract);
}
unsigned TargetTransformInfo::
getOperandsScalarizationOverhead(ArrayRef<const Value *> Args,
unsigned VF) const {
return TTIImpl->getOperandsScalarizationOverhead(Args, VF);
}
bool TargetTransformInfo::supportsEfficientVectorElementLoadStore() const {
return TTIImpl->supportsEfficientVectorElementLoadStore();
}
bool TargetTransformInfo::enableAggressiveInterleaving(bool LoopHasReductions) const {
return TTIImpl->enableAggressiveInterleaving(LoopHasReductions);
}
const TargetTransformInfo::MemCmpExpansionOptions *
TargetTransformInfo::enableMemCmpExpansion(bool IsZeroCmp) const {
return TTIImpl->enableMemCmpExpansion(IsZeroCmp);
}
bool TargetTransformInfo::enableInterleavedAccessVectorization() const {
return TTIImpl->enableInterleavedAccessVectorization();
}
bool TargetTransformInfo::enableMaskedInterleavedAccessVectorization() const {
return TTIImpl->enableMaskedInterleavedAccessVectorization();
}
bool TargetTransformInfo::isFPVectorizationPotentiallyUnsafe() const {
return TTIImpl->isFPVectorizationPotentiallyUnsafe();
}
bool TargetTransformInfo::allowsMisalignedMemoryAccesses(LLVMContext &Context,
unsigned BitWidth,
unsigned AddressSpace,
unsigned Alignment,
bool *Fast) const {
return TTIImpl->allowsMisalignedMemoryAccesses(Context, BitWidth, AddressSpace,
Alignment, Fast);
}
TargetTransformInfo::PopcntSupportKind
TargetTransformInfo::getPopcntSupport(unsigned IntTyWidthInBit) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getPopcntSupport(IntTyWidthInBit);
}
bool TargetTransformInfo::haveFastSqrt(Type *Ty) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->haveFastSqrt(Ty);
}
bool TargetTransformInfo::isFCmpOrdCheaperThanFCmpZero(Type *Ty) const {
return TTIImpl->isFCmpOrdCheaperThanFCmpZero(Ty);
}
int TargetTransformInfo::getFPOpCost(Type *Ty) const {
int Cost = TTIImpl->getFPOpCost(Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCodeSizeCost(unsigned Opcode, unsigned Idx,
const APInt &Imm,
Type *Ty) const {
int Cost = TTIImpl->getIntImmCodeSizeCost(Opcode, Idx, Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCost(const APInt &Imm, Type *Ty) const {
int Cost = TTIImpl->getIntImmCost(Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCost(unsigned Opcode, unsigned Idx,
const APInt &Imm, Type *Ty) const {
int Cost = TTIImpl->getIntImmCost(Opcode, Idx, Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCost(Intrinsic::ID IID, unsigned Idx,
const APInt &Imm, Type *Ty) const {
int Cost = TTIImpl->getIntImmCost(IID, Idx, Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned TargetTransformInfo::getNumberOfRegisters(bool Vector) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getNumberOfRegisters(Vector);
}
unsigned TargetTransformInfo::getRegisterBitWidth(bool Vector) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getRegisterBitWidth(Vector);
}
[SLP] Enable 64-bit wide vectorization on AArch64 ARM Neon has native support for half-sized vector registers (64 bits). This is beneficial for example for 2D and 3D graphics. This patch adds the option to lower MinVecRegSize from 128 via a TTI in the SLP Vectorizer. *** Performance Analysis This change was motivated by some internal benchmarks but it is also beneficial on SPEC and the LLVM testsuite. The results are with -O3 and PGO. A negative percentage is an improvement. The testsuite was run with a sample size of 4. ** SPEC * CFP2006/482.sphinx3 -3.34% A pretty hot loop is SLP vectorized resulting in nice instruction reduction. This used to be a +22% regression before rL299482. * CFP2000/177.mesa -3.34% * CINT2000/256.bzip2 +6.97% My current plan is to extend the fix in rL299482 to i16 which brings the regression down to +2.5%. There are also other problems with the codegen in this loop so there is further room for improvement. ** LLVM testsuite * SingleSource/Benchmarks/Misc/ReedSolomon -10.75% There are multiple small SLP vectorizations outside the hot code. It's a bit surprising that it adds up to 10%. Some of this may be code-layout noise. * MultiSource/Benchmarks/VersaBench/beamformer/beamformer -8.40% The opt-viewer screenshot can be seen at F3218284. We start at a colder store but the tree leads us into the hottest loop. * MultiSource/Applications/lambda-0.1.3/lambda -2.68% * MultiSource/Benchmarks/Bullet/bullet -2.18% This is using 3D vectors. * SingleSource/Benchmarks/Shootout-C++/Shootout-C++-lists +6.67% Noise, binary is unchanged. * MultiSource/Benchmarks/Ptrdist/anagram/anagram +4.90% There is an additional SLP in the cold code. The test runs for ~1sec and prints out over 2000 lines. This is most likely noise. * MultiSource/Applications/aha/aha +1.63% * MultiSource/Applications/JM/lencod/lencod +1.41% * SingleSource/Benchmarks/Misc/richards_benchmark +1.15% Differential Revision: https://reviews.llvm.org/D31965 llvm-svn: 303116
2017-05-16 05:15:01 +08:00
unsigned TargetTransformInfo::getMinVectorRegisterBitWidth() const {
return TTIImpl->getMinVectorRegisterBitWidth();
}
bool TargetTransformInfo::shouldMaximizeVectorBandwidth(bool OptSize) const {
return TTIImpl->shouldMaximizeVectorBandwidth(OptSize);
}
unsigned TargetTransformInfo::getMinimumVF(unsigned ElemWidth) const {
return TTIImpl->getMinimumVF(ElemWidth);
}
bool TargetTransformInfo::shouldConsiderAddressTypePromotion(
const Instruction &I, bool &AllowPromotionWithoutCommonHeader) const {
return TTIImpl->shouldConsiderAddressTypePromotion(
I, AllowPromotionWithoutCommonHeader);
}
unsigned TargetTransformInfo::getCacheLineSize() const {
return TTIImpl->getCacheLineSize();
}
2017-08-24 17:46:25 +08:00
llvm::Optional<unsigned> TargetTransformInfo::getCacheSize(CacheLevel Level)
const {
return TTIImpl->getCacheSize(Level);
}
llvm::Optional<unsigned> TargetTransformInfo::getCacheAssociativity(
CacheLevel Level) const {
return TTIImpl->getCacheAssociativity(Level);
}
unsigned TargetTransformInfo::getPrefetchDistance() const {
return TTIImpl->getPrefetchDistance();
}
unsigned TargetTransformInfo::getMinPrefetchStride() const {
return TTIImpl->getMinPrefetchStride();
}
unsigned TargetTransformInfo::getMaxPrefetchIterationsAhead() const {
return TTIImpl->getMaxPrefetchIterationsAhead();
}
unsigned TargetTransformInfo::getMaxInterleaveFactor(unsigned VF) const {
return TTIImpl->getMaxInterleaveFactor(VF);
}
TargetTransformInfo::OperandValueKind
TargetTransformInfo::getOperandInfo(Value *V, OperandValueProperties &OpProps) {
OperandValueKind OpInfo = OK_AnyValue;
OpProps = OP_None;
if (auto *CI = dyn_cast<ConstantInt>(V)) {
if (CI->getValue().isPowerOf2())
OpProps = OP_PowerOf2;
return OK_UniformConstantValue;
}
// A broadcast shuffle creates a uniform value.
// TODO: Add support for non-zero index broadcasts.
// TODO: Add support for different source vector width.
if (auto *ShuffleInst = dyn_cast<ShuffleVectorInst>(V))
if (ShuffleInst->isZeroEltSplat())
OpInfo = OK_UniformValue;
const Value *Splat = getSplatValue(V);
// Check for a splat of a constant or for a non uniform vector of constants
// and check if the constant(s) are all powers of two.
if (isa<ConstantVector>(V) || isa<ConstantDataVector>(V)) {
OpInfo = OK_NonUniformConstantValue;
if (Splat) {
OpInfo = OK_UniformConstantValue;
if (auto *CI = dyn_cast<ConstantInt>(Splat))
if (CI->getValue().isPowerOf2())
OpProps = OP_PowerOf2;
} else if (auto *CDS = dyn_cast<ConstantDataSequential>(V)) {
OpProps = OP_PowerOf2;
for (unsigned I = 0, E = CDS->getNumElements(); I != E; ++I) {
if (auto *CI = dyn_cast<ConstantInt>(CDS->getElementAsConstant(I)))
if (CI->getValue().isPowerOf2())
continue;
OpProps = OP_None;
break;
}
}
}
// Check for a splat of a uniform value. This is not loop aware, so return
// true only for the obviously uniform cases (argument, globalvalue)
if (Splat && (isa<Argument>(Splat) || isa<GlobalValue>(Splat)))
OpInfo = OK_UniformValue;
return OpInfo;
}
int TargetTransformInfo::getArithmeticInstrCost(
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
unsigned Opcode, Type *Ty, OperandValueKind Opd1Info,
OperandValueKind Opd2Info, OperandValueProperties Opd1PropInfo,
OperandValueProperties Opd2PropInfo,
ArrayRef<const Value *> Args) const {
int Cost = TTIImpl->getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
Opd1PropInfo, Opd2PropInfo, Args);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getShuffleCost(ShuffleKind Kind, Type *Ty, int Index,
Type *SubTp) const {
int Cost = TTIImpl->getShuffleCost(Kind, Ty, Index, SubTp);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCastInstrCost(unsigned Opcode, Type *Dst,
Type *Src, const Instruction *I) const {
assert ((I == nullptr || I->getOpcode() == Opcode) &&
"Opcode should reflect passed instruction.");
int Cost = TTIImpl->getCastInstrCost(Opcode, Dst, Src, I);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getExtractWithExtendCost(unsigned Opcode, Type *Dst,
VectorType *VecTy,
unsigned Index) const {
int Cost = TTIImpl->getExtractWithExtendCost(Opcode, Dst, VecTy, Index);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCFInstrCost(unsigned Opcode) const {
int Cost = TTIImpl->getCFInstrCost(Opcode);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
Type *CondTy, const Instruction *I) const {
assert ((I == nullptr || I->getOpcode() == Opcode) &&
"Opcode should reflect passed instruction.");
int Cost = TTIImpl->getCmpSelInstrCost(Opcode, ValTy, CondTy, I);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getVectorInstrCost(unsigned Opcode, Type *Val,
unsigned Index) const {
int Cost = TTIImpl->getVectorInstrCost(Opcode, Val, Index);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getMemoryOpCost(unsigned Opcode, Type *Src,
unsigned Alignment,
unsigned AddressSpace,
const Instruction *I) const {
assert ((I == nullptr || I->getOpcode() == Opcode) &&
"Opcode should reflect passed instruction.");
int Cost = TTIImpl->getMemoryOpCost(Opcode, Src, Alignment, AddressSpace, I);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getMaskedMemoryOpCost(unsigned Opcode, Type *Src,
unsigned Alignment,
unsigned AddressSpace) const {
int Cost =
TTIImpl->getMaskedMemoryOpCost(Opcode, Src, Alignment, AddressSpace);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getGatherScatterOpCost(unsigned Opcode, Type *DataTy,
Value *Ptr, bool VariableMask,
unsigned Alignment) const {
int Cost = TTIImpl->getGatherScatterOpCost(Opcode, DataTy, Ptr, VariableMask,
Alignment);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getInterleavedMemoryOpCost(
unsigned Opcode, Type *VecTy, unsigned Factor, ArrayRef<unsigned> Indices,
unsigned Alignment, unsigned AddressSpace, bool UseMaskForCond,
bool UseMaskForGaps) const {
int Cost = TTIImpl->getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices,
Alignment, AddressSpace,
UseMaskForCond,
UseMaskForGaps);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Type *> Tys, FastMathFlags FMF,
unsigned ScalarizationCostPassed) const {
int Cost = TTIImpl->getIntrinsicInstrCost(ID, RetTy, Tys, FMF,
ScalarizationCostPassed);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Value *> Args, FastMathFlags FMF, unsigned VF) const {
int Cost = TTIImpl->getIntrinsicInstrCost(ID, RetTy, Args, FMF, VF);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCallInstrCost(Function *F, Type *RetTy,
ArrayRef<Type *> Tys) const {
int Cost = TTIImpl->getCallInstrCost(F, RetTy, Tys);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned TargetTransformInfo::getNumberOfParts(Type *Tp) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getNumberOfParts(Tp);
}
int TargetTransformInfo::getAddressComputationCost(Type *Tp,
ScalarEvolution *SE,
const SCEV *Ptr) const {
int Cost = TTIImpl->getAddressComputationCost(Tp, SE, Ptr);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getArithmeticReductionCost(unsigned Opcode, Type *Ty,
bool IsPairwiseForm) const {
int Cost = TTIImpl->getArithmeticReductionCost(Opcode, Ty, IsPairwiseForm);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
}
int TargetTransformInfo::getMinMaxReductionCost(Type *Ty, Type *CondTy,
bool IsPairwiseForm,
bool IsUnsigned) const {
int Cost =
TTIImpl->getMinMaxReductionCost(Ty, CondTy, IsPairwiseForm, IsUnsigned);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
unsigned
TargetTransformInfo::getCostOfKeepingLiveOverCall(ArrayRef<Type *> Tys) const {
return TTIImpl->getCostOfKeepingLiveOverCall(Tys);
Costmodel: Add support for horizontal vector reductions Upcoming SLP vectorization improvements will want to be able to estimate costs of horizontal reductions. Add infrastructure to support this. We model reductions as a series of (shufflevector,add) tuples ultimately followed by an extractelement. For example, for an add-reduction of <4 x float> we could generate the following sequence: (v0, v1, v2, v3) \ \ / / \ \ / + + (v0+v2, v1+v3, undef, undef) \ / ((v0+v2) + (v1+v3), undef, undef) %rdx.shuf = shufflevector <4 x float> %rdx, <4 x float> undef, <4 x i32> <i32 2, i32 3, i32 undef, i32 undef> %bin.rdx = fadd <4 x float> %rdx, %rdx.shuf %rdx.shuf7 = shufflevector <4 x float> %bin.rdx, <4 x float> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef> %bin.rdx8 = fadd <4 x float> %bin.rdx, %rdx.shuf7 %r = extractelement <4 x float> %bin.rdx8, i32 0 This commit adds a cost model interface "getReductionCost(Opcode, Ty, Pairwise)" that will allow clients to ask for the cost of such a reduction (as backends might generate more efficient code than the cost of the individual instructions summed up). This interface is excercised by the CostModel analysis pass which looks for reduction patterns like the one above - starting at extractelements - and if it sees a matching sequence will call the cost model interface. We will also support a second form of pairwise reduction that is well supported on common architectures (haddps, vpadd, faddp). (v0, v1, v2, v3) \ / \ / (v0+v1, v2+v3, undef, undef) \ / ((v0+v1)+(v2+v3), undef, undef, undef) %rdx.shuf.0.0 = shufflevector <4 x float> %rdx, <4 x float> undef, <4 x i32> <i32 0, i32 2 , i32 undef, i32 undef> %rdx.shuf.0.1 = shufflevector <4 x float> %rdx, <4 x float> undef, <4 x i32> <i32 1, i32 3, i32 undef, i32 undef> %bin.rdx.0 = fadd <4 x float> %rdx.shuf.0.0, %rdx.shuf.0.1 %rdx.shuf.1.0 = shufflevector <4 x float> %bin.rdx.0, <4 x float> undef, <4 x i32> <i32 0, i32 undef, i32 undef, i32 undef> %rdx.shuf.1.1 = shufflevector <4 x float> %bin.rdx.0, <4 x float> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef> %bin.rdx.1 = fadd <4 x float> %rdx.shuf.1.0, %rdx.shuf.1.1 %r = extractelement <4 x float> %bin.rdx.1, i32 0 llvm-svn: 190876
2013-09-18 02:06:50 +08:00
}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
bool TargetTransformInfo::getTgtMemIntrinsic(IntrinsicInst *Inst,
MemIntrinsicInfo &Info) const {
return TTIImpl->getTgtMemIntrinsic(Inst, Info);
}
unsigned TargetTransformInfo::getAtomicMemIntrinsicMaxElementSize() const {
return TTIImpl->getAtomicMemIntrinsicMaxElementSize();
}
Value *TargetTransformInfo::getOrCreateResultFromMemIntrinsic(
IntrinsicInst *Inst, Type *ExpectedType) const {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
return TTIImpl->getOrCreateResultFromMemIntrinsic(Inst, ExpectedType);
}
Type *TargetTransformInfo::getMemcpyLoopLoweringType(LLVMContext &Context,
Value *Length,
unsigned SrcAlign,
unsigned DestAlign) const {
return TTIImpl->getMemcpyLoopLoweringType(Context, Length, SrcAlign,
DestAlign);
}
void TargetTransformInfo::getMemcpyLoopResidualLoweringType(
SmallVectorImpl<Type *> &OpsOut, LLVMContext &Context,
unsigned RemainingBytes, unsigned SrcAlign, unsigned DestAlign) const {
TTIImpl->getMemcpyLoopResidualLoweringType(OpsOut, Context, RemainingBytes,
SrcAlign, DestAlign);
}
bool TargetTransformInfo::areInlineCompatible(const Function *Caller,
const Function *Callee) const {
return TTIImpl->areInlineCompatible(Caller, Callee);
}
bool TargetTransformInfo::isIndexedLoadLegal(MemIndexedMode Mode,
Type *Ty) const {
return TTIImpl->isIndexedLoadLegal(Mode, Ty);
}
bool TargetTransformInfo::isIndexedStoreLegal(MemIndexedMode Mode,
Type *Ty) const {
return TTIImpl->isIndexedStoreLegal(Mode, Ty);
}
unsigned TargetTransformInfo::getLoadStoreVecRegBitWidth(unsigned AS) const {
return TTIImpl->getLoadStoreVecRegBitWidth(AS);
}
bool TargetTransformInfo::isLegalToVectorizeLoad(LoadInst *LI) const {
return TTIImpl->isLegalToVectorizeLoad(LI);
}
bool TargetTransformInfo::isLegalToVectorizeStore(StoreInst *SI) const {
return TTIImpl->isLegalToVectorizeStore(SI);
}
bool TargetTransformInfo::isLegalToVectorizeLoadChain(
unsigned ChainSizeInBytes, unsigned Alignment, unsigned AddrSpace) const {
return TTIImpl->isLegalToVectorizeLoadChain(ChainSizeInBytes, Alignment,
AddrSpace);
}
bool TargetTransformInfo::isLegalToVectorizeStoreChain(
unsigned ChainSizeInBytes, unsigned Alignment, unsigned AddrSpace) const {
return TTIImpl->isLegalToVectorizeStoreChain(ChainSizeInBytes, Alignment,
AddrSpace);
}
unsigned TargetTransformInfo::getLoadVectorFactor(unsigned VF,
unsigned LoadSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const {
return TTIImpl->getLoadVectorFactor(VF, LoadSize, ChainSizeInBytes, VecTy);
}
unsigned TargetTransformInfo::getStoreVectorFactor(unsigned VF,
unsigned StoreSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const {
return TTIImpl->getStoreVectorFactor(VF, StoreSize, ChainSizeInBytes, VecTy);
}
bool TargetTransformInfo::useReductionIntrinsic(unsigned Opcode,
Type *Ty, ReductionFlags Flags) const {
return TTIImpl->useReductionIntrinsic(Opcode, Ty, Flags);
}
bool TargetTransformInfo::shouldExpandReduction(const IntrinsicInst *II) const {
return TTIImpl->shouldExpandReduction(II);
}
int TargetTransformInfo::getInstructionLatency(const Instruction *I) const {
return TTIImpl->getInstructionLatency(I);
}
static bool matchPairwiseShuffleMask(ShuffleVectorInst *SI, bool IsLeft,
unsigned Level) {
// We don't need a shuffle if we just want to have element 0 in position 0 of
// the vector.
if (!SI && Level == 0 && IsLeft)
return true;
else if (!SI)
return false;
SmallVector<int, 32> Mask(SI->getType()->getVectorNumElements(), -1);
// Build a mask of 0, 2, ... (left) or 1, 3, ... (right) depending on whether
// we look at the left or right side.
for (unsigned i = 0, e = (1 << Level), val = !IsLeft; i != e; ++i, val += 2)
Mask[i] = val;
SmallVector<int, 16> ActualMask = SI->getShuffleMask();
return Mask == ActualMask;
}
namespace {
/// Kind of the reduction data.
enum ReductionKind {
RK_None, /// Not a reduction.
RK_Arithmetic, /// Binary reduction data.
RK_MinMax, /// Min/max reduction data.
RK_UnsignedMinMax, /// Unsigned min/max reduction data.
};
/// Contains opcode + LHS/RHS parts of the reduction operations.
struct ReductionData {
ReductionData() = delete;
ReductionData(ReductionKind Kind, unsigned Opcode, Value *LHS, Value *RHS)
: Opcode(Opcode), LHS(LHS), RHS(RHS), Kind(Kind) {
assert(Kind != RK_None && "expected binary or min/max reduction only.");
}
unsigned Opcode = 0;
Value *LHS = nullptr;
Value *RHS = nullptr;
ReductionKind Kind = RK_None;
bool hasSameData(ReductionData &RD) const {
return Kind == RD.Kind && Opcode == RD.Opcode;
}
};
} // namespace
static Optional<ReductionData> getReductionData(Instruction *I) {
Value *L, *R;
if (m_BinOp(m_Value(L), m_Value(R)).match(I))
return ReductionData(RK_Arithmetic, I->getOpcode(), L, R);
if (auto *SI = dyn_cast<SelectInst>(I)) {
if (m_SMin(m_Value(L), m_Value(R)).match(SI) ||
m_SMax(m_Value(L), m_Value(R)).match(SI) ||
m_OrdFMin(m_Value(L), m_Value(R)).match(SI) ||
m_OrdFMax(m_Value(L), m_Value(R)).match(SI) ||
m_UnordFMin(m_Value(L), m_Value(R)).match(SI) ||
m_UnordFMax(m_Value(L), m_Value(R)).match(SI)) {
auto *CI = cast<CmpInst>(SI->getCondition());
return ReductionData(RK_MinMax, CI->getOpcode(), L, R);
}
if (m_UMin(m_Value(L), m_Value(R)).match(SI) ||
m_UMax(m_Value(L), m_Value(R)).match(SI)) {
auto *CI = cast<CmpInst>(SI->getCondition());
return ReductionData(RK_UnsignedMinMax, CI->getOpcode(), L, R);
}
}
return llvm::None;
}
static ReductionKind matchPairwiseReductionAtLevel(Instruction *I,
unsigned Level,
unsigned NumLevels) {
// Match one level of pairwise operations.
// %rdx.shuf.0.0 = shufflevector <4 x float> %rdx, <4 x float> undef,
// <4 x i32> <i32 0, i32 2 , i32 undef, i32 undef>
// %rdx.shuf.0.1 = shufflevector <4 x float> %rdx, <4 x float> undef,
// <4 x i32> <i32 1, i32 3, i32 undef, i32 undef>
// %bin.rdx.0 = fadd <4 x float> %rdx.shuf.0.0, %rdx.shuf.0.1
if (!I)
return RK_None;
assert(I->getType()->isVectorTy() && "Expecting a vector type");
Optional<ReductionData> RD = getReductionData(I);
if (!RD)
return RK_None;
ShuffleVectorInst *LS = dyn_cast<ShuffleVectorInst>(RD->LHS);
if (!LS && Level)
return RK_None;
ShuffleVectorInst *RS = dyn_cast<ShuffleVectorInst>(RD->RHS);
if (!RS && Level)
return RK_None;
// On level 0 we can omit one shufflevector instruction.
if (!Level && !RS && !LS)
return RK_None;
// Shuffle inputs must match.
Value *NextLevelOpL = LS ? LS->getOperand(0) : nullptr;
Value *NextLevelOpR = RS ? RS->getOperand(0) : nullptr;
Value *NextLevelOp = nullptr;
if (NextLevelOpR && NextLevelOpL) {
// If we have two shuffles their operands must match.
if (NextLevelOpL != NextLevelOpR)
return RK_None;
NextLevelOp = NextLevelOpL;
} else if (Level == 0 && (NextLevelOpR || NextLevelOpL)) {
// On the first level we can omit the shufflevector <0, undef,...>. So the
// input to the other shufflevector <1, undef> must match with one of the
// inputs to the current binary operation.
// Example:
// %NextLevelOpL = shufflevector %R, <1, undef ...>
// %BinOp = fadd %NextLevelOpL, %R
if (NextLevelOpL && NextLevelOpL != RD->RHS)
return RK_None;
else if (NextLevelOpR && NextLevelOpR != RD->LHS)
return RK_None;
NextLevelOp = NextLevelOpL ? RD->RHS : RD->LHS;
} else
return RK_None;
// Check that the next levels binary operation exists and matches with the
// current one.
if (Level + 1 != NumLevels) {
Optional<ReductionData> NextLevelRD =
getReductionData(cast<Instruction>(NextLevelOp));
if (!NextLevelRD || !RD->hasSameData(*NextLevelRD))
return RK_None;
}
// Shuffle mask for pairwise operation must match.
if (matchPairwiseShuffleMask(LS, /*IsLeft=*/true, Level)) {
if (!matchPairwiseShuffleMask(RS, /*IsLeft=*/false, Level))
return RK_None;
} else if (matchPairwiseShuffleMask(RS, /*IsLeft=*/true, Level)) {
if (!matchPairwiseShuffleMask(LS, /*IsLeft=*/false, Level))
return RK_None;
} else {
return RK_None;
}
if (++Level == NumLevels)
return RD->Kind;
// Match next level.
return matchPairwiseReductionAtLevel(cast<Instruction>(NextLevelOp), Level,
NumLevels);
}
static ReductionKind matchPairwiseReduction(const ExtractElementInst *ReduxRoot,
unsigned &Opcode, Type *&Ty) {
if (!EnableReduxCost)
return RK_None;
// Need to extract the first element.
ConstantInt *CI = dyn_cast<ConstantInt>(ReduxRoot->getOperand(1));
unsigned Idx = ~0u;
if (CI)
Idx = CI->getZExtValue();
if (Idx != 0)
return RK_None;
auto *RdxStart = dyn_cast<Instruction>(ReduxRoot->getOperand(0));
if (!RdxStart)
return RK_None;
Optional<ReductionData> RD = getReductionData(RdxStart);
if (!RD)
return RK_None;
Type *VecTy = RdxStart->getType();
unsigned NumVecElems = VecTy->getVectorNumElements();
if (!isPowerOf2_32(NumVecElems))
return RK_None;
// We look for a sequence of shuffle,shuffle,add triples like the following
// that builds a pairwise reduction tree.
//
// (X0, X1, X2, X3)
// (X0 + X1, X2 + X3, undef, undef)
// ((X0 + X1) + (X2 + X3), undef, undef, undef)
//
// %rdx.shuf.0.0 = shufflevector <4 x float> %rdx, <4 x float> undef,
// <4 x i32> <i32 0, i32 2 , i32 undef, i32 undef>
// %rdx.shuf.0.1 = shufflevector <4 x float> %rdx, <4 x float> undef,
// <4 x i32> <i32 1, i32 3, i32 undef, i32 undef>
// %bin.rdx.0 = fadd <4 x float> %rdx.shuf.0.0, %rdx.shuf.0.1
// %rdx.shuf.1.0 = shufflevector <4 x float> %bin.rdx.0, <4 x float> undef,
// <4 x i32> <i32 0, i32 undef, i32 undef, i32 undef>
// %rdx.shuf.1.1 = shufflevector <4 x float> %bin.rdx.0, <4 x float> undef,
// <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef>
// %bin.rdx8 = fadd <4 x float> %rdx.shuf.1.0, %rdx.shuf.1.1
// %r = extractelement <4 x float> %bin.rdx8, i32 0
if (matchPairwiseReductionAtLevel(RdxStart, 0, Log2_32(NumVecElems)) ==
RK_None)
return RK_None;
Opcode = RD->Opcode;
Ty = VecTy;
return RD->Kind;
}
static std::pair<Value *, ShuffleVectorInst *>
getShuffleAndOtherOprd(Value *L, Value *R) {
ShuffleVectorInst *S = nullptr;
if ((S = dyn_cast<ShuffleVectorInst>(L)))
return std::make_pair(R, S);
S = dyn_cast<ShuffleVectorInst>(R);
return std::make_pair(L, S);
}
static ReductionKind
matchVectorSplittingReduction(const ExtractElementInst *ReduxRoot,
unsigned &Opcode, Type *&Ty) {
if (!EnableReduxCost)
return RK_None;
// Need to extract the first element.
ConstantInt *CI = dyn_cast<ConstantInt>(ReduxRoot->getOperand(1));
unsigned Idx = ~0u;
if (CI)
Idx = CI->getZExtValue();
if (Idx != 0)
return RK_None;
auto *RdxStart = dyn_cast<Instruction>(ReduxRoot->getOperand(0));
if (!RdxStart)
return RK_None;
Optional<ReductionData> RD = getReductionData(RdxStart);
if (!RD)
return RK_None;
Type *VecTy = ReduxRoot->getOperand(0)->getType();
unsigned NumVecElems = VecTy->getVectorNumElements();
if (!isPowerOf2_32(NumVecElems))
return RK_None;
// We look for a sequence of shuffles and adds like the following matching one
// fadd, shuffle vector pair at a time.
//
// %rdx.shuf = shufflevector <4 x float> %rdx, <4 x float> undef,
// <4 x i32> <i32 2, i32 3, i32 undef, i32 undef>
// %bin.rdx = fadd <4 x float> %rdx, %rdx.shuf
// %rdx.shuf7 = shufflevector <4 x float> %bin.rdx, <4 x float> undef,
// <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef>
// %bin.rdx8 = fadd <4 x float> %bin.rdx, %rdx.shuf7
// %r = extractelement <4 x float> %bin.rdx8, i32 0
unsigned MaskStart = 1;
Instruction *RdxOp = RdxStart;
SmallVector<int, 32> ShuffleMask(NumVecElems, 0);
unsigned NumVecElemsRemain = NumVecElems;
while (NumVecElemsRemain - 1) {
// Check for the right reduction operation.
if (!RdxOp)
return RK_None;
Optional<ReductionData> RDLevel = getReductionData(RdxOp);
if (!RDLevel || !RDLevel->hasSameData(*RD))
return RK_None;
Value *NextRdxOp;
ShuffleVectorInst *Shuffle;
std::tie(NextRdxOp, Shuffle) =
getShuffleAndOtherOprd(RDLevel->LHS, RDLevel->RHS);
// Check the current reduction operation and the shuffle use the same value.
if (Shuffle == nullptr)
return RK_None;
if (Shuffle->getOperand(0) != NextRdxOp)
return RK_None;
// Check that shuffle masks matches.
for (unsigned j = 0; j != MaskStart; ++j)
ShuffleMask[j] = MaskStart + j;
// Fill the rest of the mask with -1 for undef.
std::fill(&ShuffleMask[MaskStart], ShuffleMask.end(), -1);
SmallVector<int, 16> Mask = Shuffle->getShuffleMask();
if (ShuffleMask != Mask)
return RK_None;
RdxOp = dyn_cast<Instruction>(NextRdxOp);
NumVecElemsRemain /= 2;
MaskStart *= 2;
}
Opcode = RD->Opcode;
Ty = VecTy;
return RD->Kind;
}
int TargetTransformInfo::getInstructionThroughput(const Instruction *I) const {
switch (I->getOpcode()) {
case Instruction::GetElementPtr:
return getUserCost(I);
case Instruction::Ret:
case Instruction::PHI:
case Instruction::Br: {
return getCFInstrCost(I->getOpcode());
}
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
TargetTransformInfo::OperandValueKind Op1VK, Op2VK;
TargetTransformInfo::OperandValueProperties Op1VP, Op2VP;
Op1VK = getOperandInfo(I->getOperand(0), Op1VP);
Op2VK = getOperandInfo(I->getOperand(1), Op2VP);
SmallVector<const Value *, 2> Operands(I->operand_values());
return getArithmeticInstrCost(I->getOpcode(), I->getType(), Op1VK, Op2VK,
Op1VP, Op2VP, Operands);
}
case Instruction::Select: {
const SelectInst *SI = cast<SelectInst>(I);
Type *CondTy = SI->getCondition()->getType();
return getCmpSelInstrCost(I->getOpcode(), I->getType(), CondTy, I);
}
case Instruction::ICmp:
case Instruction::FCmp: {
Type *ValTy = I->getOperand(0)->getType();
return getCmpSelInstrCost(I->getOpcode(), ValTy, I->getType(), I);
}
case Instruction::Store: {
const StoreInst *SI = cast<StoreInst>(I);
Type *ValTy = SI->getValueOperand()->getType();
return getMemoryOpCost(I->getOpcode(), ValTy,
SI->getAlignment(),
SI->getPointerAddressSpace(), I);
}
case Instruction::Load: {
const LoadInst *LI = cast<LoadInst>(I);
return getMemoryOpCost(I->getOpcode(), I->getType(),
LI->getAlignment(),
LI->getPointerAddressSpace(), I);
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast:
case Instruction::AddrSpaceCast: {
Type *SrcTy = I->getOperand(0)->getType();
return getCastInstrCost(I->getOpcode(), I->getType(), SrcTy, I);
}
case Instruction::ExtractElement: {
const ExtractElementInst * EEI = cast<ExtractElementInst>(I);
ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1));
unsigned Idx = -1;
if (CI)
Idx = CI->getZExtValue();
// Try to match a reduction sequence (series of shufflevector and vector
// adds followed by a extractelement).
unsigned ReduxOpCode;
Type *ReduxType;
switch (matchVectorSplittingReduction(EEI, ReduxOpCode, ReduxType)) {
case RK_Arithmetic:
return getArithmeticReductionCost(ReduxOpCode, ReduxType,
/*IsPairwiseForm=*/false);
case RK_MinMax:
return getMinMaxReductionCost(
ReduxType, CmpInst::makeCmpResultType(ReduxType),
/*IsPairwiseForm=*/false, /*IsUnsigned=*/false);
case RK_UnsignedMinMax:
return getMinMaxReductionCost(
ReduxType, CmpInst::makeCmpResultType(ReduxType),
/*IsPairwiseForm=*/false, /*IsUnsigned=*/true);
case RK_None:
break;
}
switch (matchPairwiseReduction(EEI, ReduxOpCode, ReduxType)) {
case RK_Arithmetic:
return getArithmeticReductionCost(ReduxOpCode, ReduxType,
/*IsPairwiseForm=*/true);
case RK_MinMax:
return getMinMaxReductionCost(
ReduxType, CmpInst::makeCmpResultType(ReduxType),
/*IsPairwiseForm=*/true, /*IsUnsigned=*/false);
case RK_UnsignedMinMax:
return getMinMaxReductionCost(
ReduxType, CmpInst::makeCmpResultType(ReduxType),
/*IsPairwiseForm=*/true, /*IsUnsigned=*/true);
case RK_None:
break;
}
return getVectorInstrCost(I->getOpcode(),
EEI->getOperand(0)->getType(), Idx);
}
case Instruction::InsertElement: {
const InsertElementInst * IE = cast<InsertElementInst>(I);
ConstantInt *CI = dyn_cast<ConstantInt>(IE->getOperand(2));
unsigned Idx = -1;
if (CI)
Idx = CI->getZExtValue();
return getVectorInstrCost(I->getOpcode(),
IE->getType(), Idx);
}
case Instruction::ShuffleVector: {
const ShuffleVectorInst *Shuffle = cast<ShuffleVectorInst>(I);
Type *Ty = Shuffle->getType();
Type *SrcTy = Shuffle->getOperand(0)->getType();
// TODO: Identify and add costs for insert subvector, etc.
int SubIndex;
if (Shuffle->isExtractSubvectorMask(SubIndex))
return TTIImpl->getShuffleCost(SK_ExtractSubvector, SrcTy, SubIndex, Ty);
if (Shuffle->changesLength())
return -1;
if (Shuffle->isIdentity())
return 0;
if (Shuffle->isReverse())
return TTIImpl->getShuffleCost(SK_Reverse, Ty, 0, nullptr);
if (Shuffle->isSelect())
return TTIImpl->getShuffleCost(SK_Select, Ty, 0, nullptr);
if (Shuffle->isTranspose())
return TTIImpl->getShuffleCost(SK_Transpose, Ty, 0, nullptr);
if (Shuffle->isZeroEltSplat())
return TTIImpl->getShuffleCost(SK_Broadcast, Ty, 0, nullptr);
if (Shuffle->isSingleSource())
return TTIImpl->getShuffleCost(SK_PermuteSingleSrc, Ty, 0, nullptr);
return TTIImpl->getShuffleCost(SK_PermuteTwoSrc, Ty, 0, nullptr);
}
case Instruction::Call:
if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
SmallVector<Value *, 4> Args(II->arg_operands());
FastMathFlags FMF;
if (auto *FPMO = dyn_cast<FPMathOperator>(II))
FMF = FPMO->getFastMathFlags();
return getIntrinsicInstrCost(II->getIntrinsicID(), II->getType(),
Args, FMF);
}
return -1;
default:
// We don't have any information on this instruction.
return -1;
}
}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
TargetTransformInfo::Concept::~Concept() {}
TargetIRAnalysis::TargetIRAnalysis() : TTICallback(&getDefaultTTI) {}
TargetIRAnalysis::TargetIRAnalysis(
std::function<Result(const Function &)> TTICallback)
: TTICallback(std::move(TTICallback)) {}
TargetIRAnalysis::Result TargetIRAnalysis::run(const Function &F,
FunctionAnalysisManager &) {
return TTICallback(F);
}
[PM] Change the static object whose address is used to uniquely identify analyses to have a common type which is enforced rather than using a char object and a `void *` type when used as an identifier. This has a number of advantages. First, it at least helps some of the confusion raised in Justin Lebar's code review of why `void *` was being used everywhere by having a stronger type that connects to documentation about this. However, perhaps more importantly, it addresses a serious issue where the alignment of these pointer-like identifiers was unknown. This made it hard to use them in pointer-like data structures. We were already dodging this in dangerous ways to create the "all analyses" entry. In a subsequent patch I attempted to use these with TinyPtrVector and things fell apart in a very bad way. And it isn't just a compile time or type system issue. Worse than that, the actual alignment of these pointer-like opaque identifiers wasn't guaranteed to be a useful alignment as they were just characters. This change introduces a type to use as the "key" object whose address forms the opaque identifier. This both forces the objects to have proper alignment, and provides type checking that we get it right everywhere. It also makes the types somewhat less mysterious than `void *`. We could go one step further and introduce a truly opaque pointer-like type to return from the `ID()` static function rather than returning `AnalysisKey *`, but that didn't seem to be a clear win so this is just the initial change to get to a reliably typed and aligned object serving is a key for all the analyses. Thanks to Richard Smith and Justin Lebar for helping pick plausible names and avoid making this refactoring many times. =] And thanks to Sean for the super fast review! While here, I've tried to move away from the "PassID" nomenclature entirely as it wasn't really helping and is overloaded with old pass manager constructs. Now we have IDs for analyses, and key objects whose address can be used as IDs. Where possible and clear I've shortened this to just "ID". In a few places I kept "AnalysisID" to make it clear what was being identified. Differential Revision: https://reviews.llvm.org/D27031 llvm-svn: 287783
2016-11-24 01:53:26 +08:00
AnalysisKey TargetIRAnalysis::Key;
TargetIRAnalysis::Result TargetIRAnalysis::getDefaultTTI(const Function &F) {
return Result(F.getParent()->getDataLayout());
}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
// Register the basic pass.
INITIALIZE_PASS(TargetTransformInfoWrapperPass, "tti",
"Target Transform Information", false, true)
char TargetTransformInfoWrapperPass::ID = 0;
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
void TargetTransformInfoWrapperPass::anchor() {}
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
TargetTransformInfoWrapperPass::TargetTransformInfoWrapperPass()
: ImmutablePass(ID) {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
initializeTargetTransformInfoWrapperPassPass(
*PassRegistry::getPassRegistry());
}
TargetTransformInfoWrapperPass::TargetTransformInfoWrapperPass(
TargetIRAnalysis TIRA)
: ImmutablePass(ID), TIRA(std::move(TIRA)) {
[PM] Change the core design of the TTI analysis to use a polymorphic type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
2015-01-31 11:43:40 +08:00
initializeTargetTransformInfoWrapperPassPass(
*PassRegistry::getPassRegistry());
}
TargetTransformInfo &TargetTransformInfoWrapperPass::getTTI(const Function &F) {
FunctionAnalysisManager DummyFAM;
TTI = TIRA.run(F, DummyFAM);
return *TTI;
}
ImmutablePass *
llvm::createTargetTransformInfoWrapperPass(TargetIRAnalysis TIRA) {
return new TargetTransformInfoWrapperPass(std::move(TIRA));
}