llvm-project/llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp

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//===-- AMDGPUTargetMachine.cpp - TargetMachine for hw codegen targets-----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// \file
/// \brief The AMDGPU target machine contains all of the hardware specific
/// information needed to emit code for R600 and SI GPUs.
//
//===----------------------------------------------------------------------===//
#include "AMDGPUTargetMachine.h"
#include "AMDGPU.h"
#include "AMDGPUAliasAnalysis.h"
#include "AMDGPUCallLowering.h"
#include "AMDGPUInstructionSelector.h"
#include "AMDGPULegalizerInfo.h"
#include "AMDGPUMacroFusion.h"
#include "AMDGPUTargetObjectFile.h"
#include "AMDGPUTargetTransformInfo.h"
#include "GCNIterativeScheduler.h"
#include "GCNSchedStrategy.h"
#include "R600MachineScheduler.h"
#include "SIMachineScheduler.h"
#include "llvm/CodeGen/GlobalISel/IRTranslator.h"
#include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
#include "llvm/CodeGen/GlobalISel/Legalizer.h"
#include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/IPO/AlwaysInliner.h"
#include "llvm/Transforms/IPO/PassManagerBuilder.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Scalar/GVN.h"
#include "llvm/Transforms/Vectorize.h"
#include <memory>
using namespace llvm;
static cl::opt<bool> EnableR600StructurizeCFG(
"r600-ir-structurize",
cl::desc("Use StructurizeCFG IR pass"),
cl::init(true));
static cl::opt<bool> EnableSROA(
"amdgpu-sroa",
cl::desc("Run SROA after promote alloca pass"),
cl::ReallyHidden,
cl::init(true));
static cl::opt<bool>
EnableEarlyIfConversion("amdgpu-early-ifcvt", cl::Hidden,
cl::desc("Run early if-conversion"),
cl::init(false));
static cl::opt<bool> EnableR600IfConvert(
"r600-if-convert",
cl::desc("Use if conversion pass"),
cl::ReallyHidden,
cl::init(true));
// Option to disable vectorizer for tests.
static cl::opt<bool> EnableLoadStoreVectorizer(
"amdgpu-load-store-vectorizer",
cl::desc("Enable load store vectorizer"),
cl::init(true),
cl::Hidden);
// Option to to control global loads scalarization
static cl::opt<bool> ScalarizeGlobal(
"amdgpu-scalarize-global-loads",
cl::desc("Enable global load scalarization"),
cl::init(true),
cl::Hidden);
// Option to run internalize pass.
static cl::opt<bool> InternalizeSymbols(
"amdgpu-internalize-symbols",
cl::desc("Enable elimination of non-kernel functions and unused globals"),
cl::init(false),
cl::Hidden);
// Option to inline all early.
static cl::opt<bool> EarlyInlineAll(
"amdgpu-early-inline-all",
cl::desc("Inline all functions early"),
cl::init(false),
cl::Hidden);
[ADMGPU] SDWA peephole optimization pass. Summary: First iteration of SDWA peephole. This pass tries to combine several instruction into one SDWA instruction. E.g. it converts: ''' V_LSHRREV_B32_e32 %vreg0, 16, %vreg1 V_ADD_I32_e32 %vreg2, %vreg0, %vreg3 V_LSHLREV_B32_e32 %vreg4, 16, %vreg2 ''' Into: ''' V_ADD_I32_sdwa %vreg4, %vreg1, %vreg3 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:WORD_1 src1_sel:DWORD ''' Pass structure: 1. Iterate over machine instruction in basic block and try to apply "SDWA patterns" to each of them. SDWA patterns match machine instruction into either source or destination SDWA operand. E.g. ''' V_LSHRREV_B32_e32 %vreg0, 16, %vreg1''' is matched to source SDWA operand '''%vreg1 src_sel:WORD_1'''. 2. Iterate over found SDWA operands and find instruction that could be potentially coverted into SDWA. E.g. for source SDWA operand potential instruction are all instruction in this basic block that uses '''%vreg0''' 3. Iterate over all potential instructions and check if they can be converted into SDWA. 4. Convert instructions to SDWA. This review contains basic implementation of SDWA peephole pass. This pass requires additional testing fot both correctness and performance (no performance testing done). There are several ways this pass can be improved: 1. Make this pass work on whole function not only basic block. As I can see this can be done right now without changes to pass. 2. Introduce more SDWA patterns 3. Introduce mnemonics to limit when SDWA patterns should apply Reviewers: vpykhtin, alex-t, arsenm, rampitec Subscribers: wdng, nhaehnle, mgorny Differential Revision: https://reviews.llvm.org/D30038 llvm-svn: 298365
2017-03-21 20:51:34 +08:00
static cl::opt<bool> EnableSDWAPeephole(
"amdgpu-sdwa-peephole",
cl::desc("Enable SDWA peepholer"),
cl::init(true));
[ADMGPU] SDWA peephole optimization pass. Summary: First iteration of SDWA peephole. This pass tries to combine several instruction into one SDWA instruction. E.g. it converts: ''' V_LSHRREV_B32_e32 %vreg0, 16, %vreg1 V_ADD_I32_e32 %vreg2, %vreg0, %vreg3 V_LSHLREV_B32_e32 %vreg4, 16, %vreg2 ''' Into: ''' V_ADD_I32_sdwa %vreg4, %vreg1, %vreg3 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:WORD_1 src1_sel:DWORD ''' Pass structure: 1. Iterate over machine instruction in basic block and try to apply "SDWA patterns" to each of them. SDWA patterns match machine instruction into either source or destination SDWA operand. E.g. ''' V_LSHRREV_B32_e32 %vreg0, 16, %vreg1''' is matched to source SDWA operand '''%vreg1 src_sel:WORD_1'''. 2. Iterate over found SDWA operands and find instruction that could be potentially coverted into SDWA. E.g. for source SDWA operand potential instruction are all instruction in this basic block that uses '''%vreg0''' 3. Iterate over all potential instructions and check if they can be converted into SDWA. 4. Convert instructions to SDWA. This review contains basic implementation of SDWA peephole pass. This pass requires additional testing fot both correctness and performance (no performance testing done). There are several ways this pass can be improved: 1. Make this pass work on whole function not only basic block. As I can see this can be done right now without changes to pass. 2. Introduce more SDWA patterns 3. Introduce mnemonics to limit when SDWA patterns should apply Reviewers: vpykhtin, alex-t, arsenm, rampitec Subscribers: wdng, nhaehnle, mgorny Differential Revision: https://reviews.llvm.org/D30038 llvm-svn: 298365
2017-03-21 20:51:34 +08:00
// Enable address space based alias analysis
static cl::opt<bool> EnableAMDGPUAliasAnalysis("enable-amdgpu-aa", cl::Hidden,
cl::desc("Enable AMDGPU Alias Analysis"),
cl::init(true));
// Option to enable new waitcnt insertion pass.
static cl::opt<bool> EnableSIInsertWaitcntsPass(
"enable-si-insert-waitcnts",
cl::desc("Use new waitcnt insertion pass"),
cl::init(true));
// Option to run late CFG structurizer
static cl::opt<bool, true> LateCFGStructurize(
"amdgpu-late-structurize",
cl::desc("Enable late CFG structurization"),
cl::location(AMDGPUTargetMachine::EnableLateStructurizeCFG),
cl::Hidden);
static cl::opt<bool> EnableAMDGPUFunctionCalls(
"amdgpu-function-calls",
cl::Hidden,
cl::desc("Enable AMDGPU function call support"),
cl::init(false));
// Enable lib calls simplifications
static cl::opt<bool> EnableLibCallSimplify(
"amdgpu-simplify-libcall",
cl::desc("Enable mdgpu library simplifications"),
cl::init(true),
cl::Hidden);
2015-06-13 11:28:10 +08:00
extern "C" void LLVMInitializeAMDGPUTarget() {
// Register the target
RegisterTargetMachine<R600TargetMachine> X(getTheAMDGPUTarget());
RegisterTargetMachine<GCNTargetMachine> Y(getTheGCNTarget());
PassRegistry *PR = PassRegistry::getPassRegistry();
initializeR600ClauseMergePassPass(*PR);
initializeR600ControlFlowFinalizerPass(*PR);
initializeR600PacketizerPass(*PR);
initializeR600ExpandSpecialInstrsPassPass(*PR);
initializeR600VectorRegMergerPass(*PR);
initializeAMDGPUDAGToDAGISelPass(*PR);
initializeSILowerI1CopiesPass(*PR);
initializeSIFixSGPRCopiesPass(*PR);
initializeSIFixVGPRCopiesPass(*PR);
initializeSIFoldOperandsPass(*PR);
[ADMGPU] SDWA peephole optimization pass. Summary: First iteration of SDWA peephole. This pass tries to combine several instruction into one SDWA instruction. E.g. it converts: ''' V_LSHRREV_B32_e32 %vreg0, 16, %vreg1 V_ADD_I32_e32 %vreg2, %vreg0, %vreg3 V_LSHLREV_B32_e32 %vreg4, 16, %vreg2 ''' Into: ''' V_ADD_I32_sdwa %vreg4, %vreg1, %vreg3 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:WORD_1 src1_sel:DWORD ''' Pass structure: 1. Iterate over machine instruction in basic block and try to apply "SDWA patterns" to each of them. SDWA patterns match machine instruction into either source or destination SDWA operand. E.g. ''' V_LSHRREV_B32_e32 %vreg0, 16, %vreg1''' is matched to source SDWA operand '''%vreg1 src_sel:WORD_1'''. 2. Iterate over found SDWA operands and find instruction that could be potentially coverted into SDWA. E.g. for source SDWA operand potential instruction are all instruction in this basic block that uses '''%vreg0''' 3. Iterate over all potential instructions and check if they can be converted into SDWA. 4. Convert instructions to SDWA. This review contains basic implementation of SDWA peephole pass. This pass requires additional testing fot both correctness and performance (no performance testing done). There are several ways this pass can be improved: 1. Make this pass work on whole function not only basic block. As I can see this can be done right now without changes to pass. 2. Introduce more SDWA patterns 3. Introduce mnemonics to limit when SDWA patterns should apply Reviewers: vpykhtin, alex-t, arsenm, rampitec Subscribers: wdng, nhaehnle, mgorny Differential Revision: https://reviews.llvm.org/D30038 llvm-svn: 298365
2017-03-21 20:51:34 +08:00
initializeSIPeepholeSDWAPass(*PR);
initializeSIShrinkInstructionsPass(*PR);
initializeSIOptimizeExecMaskingPreRAPass(*PR);
initializeSILoadStoreOptimizerPass(*PR);
initializeAMDGPUAlwaysInlinePass(*PR);
initializeAMDGPUAnnotateKernelFeaturesPass(*PR);
initializeAMDGPUAnnotateUniformValuesPass(*PR);
initializeAMDGPUArgumentUsageInfoPass(*PR);
initializeAMDGPULowerIntrinsicsPass(*PR);
initializeAMDGPUOpenCLEnqueuedBlockLoweringPass(*PR);
initializeAMDGPUPromoteAllocaPass(*PR);
initializeAMDGPUCodeGenPreparePass(*PR);
initializeAMDGPURewriteOutArgumentsPass(*PR);
initializeAMDGPUUnifyMetadataPass(*PR);
initializeSIAnnotateControlFlowPass(*PR);
initializeSIInsertWaitsPass(*PR);
initializeSIInsertWaitcntsPass(*PR);
initializeSIWholeQuadModePass(*PR);
initializeSILowerControlFlowPass(*PR);
initializeSIInsertSkipsPass(*PR);
initializeSIMemoryLegalizerPass(*PR);
initializeSIDebuggerInsertNopsPass(*PR);
initializeSIOptimizeExecMaskingPass(*PR);
[AMDGPU] Add support for Whole Wavefront Mode Summary: Whole Wavefront Wode (WWM) is similar to WQM, except that all of the lanes are always enabled, regardless of control flow. This is required for implementing wavefront reductions in non-uniform control flow, where we need to use the inactive lanes to propagate intermediate results, so they need to be enabled. We need to propagate WWM to uses (unless they're explicitly marked as exact) so that they also propagate intermediate results correctly. We do the analysis and exec mask munging during the WQM pass, since there are interactions with WQM for things that require both WQM and WWM. For simplicity, WWM is entirely block-local -- blocks are never WWM on entry or exit of a block, and WWM is not propagated to the block level. This means that computations involving WWM cannot involve control flow, but we only ever plan to use WWM for a few limited purposes (none of which involve control flow) anyways. Shaders can ask for WWM using the @llvm.amdgcn.wwm intrinsic. There isn't yet a way to turn WWM off -- that will be added in a future change. Finally, it turns out that turning on inactive lanes causes a number of problems with register allocation. While the best long-term solution seems like teaching LLVM's register allocator about predication, for now we need to add some hacks to prevent ourselves from getting into trouble due to constraints that aren't currently expressed in LLVM. For the gory details, see the comments at the top of SIFixWWMLiveness.cpp. Reviewers: arsenm, nhaehnle, tpr Subscribers: kzhuravl, wdng, mgorny, yaxunl, dstuttard, t-tye, llvm-commits Differential Revision: https://reviews.llvm.org/D35524 llvm-svn: 310087
2017-08-05 02:36:52 +08:00
initializeSIFixWWMLivenessPass(*PR);
initializeAMDGPUUnifyDivergentExitNodesPass(*PR);
initializeAMDGPUAAWrapperPassPass(*PR);
initializeAMDGPUUseNativeCallsPass(*PR);
initializeAMDGPUSimplifyLibCallsPass(*PR);
initializeAMDGPUInlinerPass(*PR);
}
static std::unique_ptr<TargetLoweringObjectFile> createTLOF(const Triple &TT) {
return llvm::make_unique<AMDGPUTargetObjectFile>();
}
static ScheduleDAGInstrs *createR600MachineScheduler(MachineSchedContext *C) {
return new ScheduleDAGMILive(C, llvm::make_unique<R600SchedStrategy>());
}
static ScheduleDAGInstrs *createSIMachineScheduler(MachineSchedContext *C) {
return new SIScheduleDAGMI(C);
}
static ScheduleDAGInstrs *
createGCNMaxOccupancyMachineScheduler(MachineSchedContext *C) {
ScheduleDAGMILive *DAG =
new GCNScheduleDAGMILive(C, make_unique<GCNMaxOccupancySchedStrategy>(C));
DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
DAG->addMutation(createStoreClusterDAGMutation(DAG->TII, DAG->TRI));
DAG->addMutation(createAMDGPUMacroFusionDAGMutation());
return DAG;
}
static ScheduleDAGInstrs *
createIterativeGCNMaxOccupancyMachineScheduler(MachineSchedContext *C) {
auto DAG = new GCNIterativeScheduler(C,
GCNIterativeScheduler::SCHEDULE_LEGACYMAXOCCUPANCY);
DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
DAG->addMutation(createStoreClusterDAGMutation(DAG->TII, DAG->TRI));
return DAG;
}
static ScheduleDAGInstrs *createMinRegScheduler(MachineSchedContext *C) {
return new GCNIterativeScheduler(C,
GCNIterativeScheduler::SCHEDULE_MINREGFORCED);
}
static MachineSchedRegistry
R600SchedRegistry("r600", "Run R600's custom scheduler",
createR600MachineScheduler);
static MachineSchedRegistry
SISchedRegistry("si", "Run SI's custom scheduler",
createSIMachineScheduler);
static MachineSchedRegistry
GCNMaxOccupancySchedRegistry("gcn-max-occupancy",
"Run GCN scheduler to maximize occupancy",
createGCNMaxOccupancyMachineScheduler);
static MachineSchedRegistry
IterativeGCNMaxOccupancySchedRegistry("gcn-max-occupancy-experimental",
"Run GCN scheduler to maximize occupancy (experimental)",
createIterativeGCNMaxOccupancyMachineScheduler);
static MachineSchedRegistry
GCNMinRegSchedRegistry("gcn-minreg",
"Run GCN iterative scheduler for minimal register usage (experimental)",
createMinRegScheduler);
static StringRef computeDataLayout(const Triple &TT) {
if (TT.getArch() == Triple::r600) {
// 32-bit pointers.
if (TT.getEnvironmentName() == "amdgiz" ||
TT.getEnvironmentName() == "amdgizcl")
return "e-p:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
"-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-A5";
return "e-p:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
"-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64";
}
// 32-bit private, local, and region pointers. 64-bit global, constant and
// flat.
if (TT.getEnvironmentName() == "amdgiz" ||
TT.getEnvironmentName() == "amdgizcl")
return "e-p:64:64-p1:64:64-p2:64:64-p3:32:32-p4:32:32-p5:32:32"
"-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
"-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-A5";
return "e-p:32:32-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32"
"-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
"-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64";
}
LLVM_READNONE
static StringRef getGPUOrDefault(const Triple &TT, StringRef GPU) {
if (!GPU.empty())
return GPU;
if (TT.getArch() == Triple::amdgcn)
return "generic";
return "r600";
}
static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
// The AMDGPU toolchain only supports generating shared objects, so we
// must always use PIC.
return Reloc::PIC_;
}
static CodeModel::Model getEffectiveCodeModel(Optional<CodeModel::Model> CM) {
if (CM)
return *CM;
return CodeModel::Small;
}
AMDGPUTargetMachine::AMDGPUTargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
TargetOptions Options,
Optional<Reloc::Model> RM,
Optional<CodeModel::Model> CM,
CodeGenOpt::Level OptLevel)
: LLVMTargetMachine(T, computeDataLayout(TT), TT, getGPUOrDefault(TT, CPU),
FS, Options, getEffectiveRelocModel(RM),
getEffectiveCodeModel(CM), OptLevel),
TLOF(createTLOF(getTargetTriple())) {
AS = AMDGPU::getAMDGPUAS(TT);
initAsmInfo();
}
AMDGPUTargetMachine::~AMDGPUTargetMachine() = default;
bool AMDGPUTargetMachine::EnableLateStructurizeCFG = false;
StringRef AMDGPUTargetMachine::getGPUName(const Function &F) const {
Attribute GPUAttr = F.getFnAttribute("target-cpu");
return GPUAttr.hasAttribute(Attribute::None) ?
getTargetCPU() : GPUAttr.getValueAsString();
}
StringRef AMDGPUTargetMachine::getFeatureString(const Function &F) const {
Attribute FSAttr = F.getFnAttribute("target-features");
return FSAttr.hasAttribute(Attribute::None) ?
getTargetFeatureString() :
FSAttr.getValueAsString();
}
static ImmutablePass *createAMDGPUExternalAAWrapperPass() {
return createExternalAAWrapperPass([](Pass &P, Function &, AAResults &AAR) {
if (auto *WrapperPass = P.getAnalysisIfAvailable<AMDGPUAAWrapperPass>())
AAR.addAAResult(WrapperPass->getResult());
});
}
/// Predicate for Internalize pass.
static bool mustPreserveGV(const GlobalValue &GV) {
if (const Function *F = dyn_cast<Function>(&GV))
return F->isDeclaration() || AMDGPU::isEntryFunctionCC(F->getCallingConv());
return !GV.use_empty();
}
void AMDGPUTargetMachine::adjustPassManager(PassManagerBuilder &Builder) {
Builder.DivergentTarget = true;
bool EnableOpt = getOptLevel() > CodeGenOpt::None;
bool Internalize = InternalizeSymbols;
bool EarlyInline = EarlyInlineAll && EnableOpt && !EnableAMDGPUFunctionCalls;
bool AMDGPUAA = EnableAMDGPUAliasAnalysis && EnableOpt;
bool LibCallSimplify = EnableLibCallSimplify && EnableOpt;
if (EnableAMDGPUFunctionCalls) {
delete Builder.Inliner;
Builder.Inliner = createAMDGPUFunctionInliningPass();
}
if (Internalize) {
// If we're generating code, we always have the whole program available. The
// relocations expected for externally visible functions aren't supported,
// so make sure every non-entry function is hidden.
Builder.addExtension(
PassManagerBuilder::EP_EnabledOnOptLevel0,
[](const PassManagerBuilder &, legacy::PassManagerBase &PM) {
PM.add(createInternalizePass(mustPreserveGV));
});
}
Builder.addExtension(
PassManagerBuilder::EP_ModuleOptimizerEarly,
[Internalize, EarlyInline, AMDGPUAA](const PassManagerBuilder &,
legacy::PassManagerBase &PM) {
if (AMDGPUAA) {
PM.add(createAMDGPUAAWrapperPass());
PM.add(createAMDGPUExternalAAWrapperPass());
}
PM.add(createAMDGPUUnifyMetadataPass());
if (Internalize) {
PM.add(createInternalizePass(mustPreserveGV));
PM.add(createGlobalDCEPass());
}
if (EarlyInline)
PM.add(createAMDGPUAlwaysInlinePass(false));
});
const auto &Opt = Options;
Builder.addExtension(
PassManagerBuilder::EP_EarlyAsPossible,
[AMDGPUAA, LibCallSimplify, &Opt](const PassManagerBuilder &,
legacy::PassManagerBase &PM) {
if (AMDGPUAA) {
PM.add(createAMDGPUAAWrapperPass());
PM.add(createAMDGPUExternalAAWrapperPass());
}
PM.add(llvm::createAMDGPUUseNativeCallsPass());
if (LibCallSimplify)
PM.add(llvm::createAMDGPUSimplifyLibCallsPass(Opt));
});
Builder.addExtension(
PassManagerBuilder::EP_CGSCCOptimizerLate,
[](const PassManagerBuilder &, legacy::PassManagerBase &PM) {
// Add infer address spaces pass to the opt pipeline after inlining
// but before SROA to increase SROA opportunities.
PM.add(createInferAddressSpacesPass());
});
}
//===----------------------------------------------------------------------===//
// R600 Target Machine (R600 -> Cayman)
//===----------------------------------------------------------------------===//
R600TargetMachine::R600TargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
TargetOptions Options,
Optional<Reloc::Model> RM,
Optional<CodeModel::Model> CM,
CodeGenOpt::Level OL, bool JIT)
: AMDGPUTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL) {
setRequiresStructuredCFG(true);
}
const R600Subtarget *R600TargetMachine::getSubtargetImpl(
const Function &F) const {
StringRef GPU = getGPUName(F);
StringRef FS = getFeatureString(F);
SmallString<128> SubtargetKey(GPU);
SubtargetKey.append(FS);
auto &I = SubtargetMap[SubtargetKey];
if (!I) {
// This needs to be done before we create a new subtarget since any
// creation will depend on the TM and the code generation flags on the
// function that reside in TargetOptions.
resetTargetOptions(F);
I = llvm::make_unique<R600Subtarget>(TargetTriple, GPU, FS, *this);
}
return I.get();
}
//===----------------------------------------------------------------------===//
// GCN Target Machine (SI+)
//===----------------------------------------------------------------------===//
GCNTargetMachine::GCNTargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
TargetOptions Options,
Optional<Reloc::Model> RM,
Optional<CodeModel::Model> CM,
CodeGenOpt::Level OL, bool JIT)
: AMDGPUTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL) {}
const SISubtarget *GCNTargetMachine::getSubtargetImpl(const Function &F) const {
StringRef GPU = getGPUName(F);
StringRef FS = getFeatureString(F);
SmallString<128> SubtargetKey(GPU);
SubtargetKey.append(FS);
auto &I = SubtargetMap[SubtargetKey];
if (!I) {
// This needs to be done before we create a new subtarget since any
// creation will depend on the TM and the code generation flags on the
// function that reside in TargetOptions.
resetTargetOptions(F);
I = llvm::make_unique<SISubtarget>(TargetTriple, GPU, FS, *this);
}
I->setScalarizeGlobalBehavior(ScalarizeGlobal);
return I.get();
}
//===----------------------------------------------------------------------===//
// AMDGPU Pass Setup
//===----------------------------------------------------------------------===//
namespace {
class AMDGPUPassConfig : public TargetPassConfig {
public:
AMDGPUPassConfig(LLVMTargetMachine &TM, PassManagerBase &PM)
: TargetPassConfig(TM, PM) {
// Exceptions and StackMaps are not supported, so these passes will never do
// anything.
disablePass(&StackMapLivenessID);
disablePass(&FuncletLayoutID);
}
AMDGPUTargetMachine &getAMDGPUTargetMachine() const {
return getTM<AMDGPUTargetMachine>();
}
ScheduleDAGInstrs *
createMachineScheduler(MachineSchedContext *C) const override {
ScheduleDAGMILive *DAG = createGenericSchedLive(C);
DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
DAG->addMutation(createStoreClusterDAGMutation(DAG->TII, DAG->TRI));
return DAG;
}
void addEarlyCSEOrGVNPass();
void addStraightLineScalarOptimizationPasses();
void addIRPasses() override;
void addCodeGenPrepare() override;
bool addPreISel() override;
bool addInstSelector() override;
bool addGCPasses() override;
};
class R600PassConfig final : public AMDGPUPassConfig {
public:
R600PassConfig(LLVMTargetMachine &TM, PassManagerBase &PM)
: AMDGPUPassConfig(TM, PM) {}
ScheduleDAGInstrs *createMachineScheduler(
MachineSchedContext *C) const override {
return createR600MachineScheduler(C);
}
bool addPreISel() override;
bool addInstSelector() override;
void addPreRegAlloc() override;
void addPreSched2() override;
void addPreEmitPass() override;
};
class GCNPassConfig final : public AMDGPUPassConfig {
public:
GCNPassConfig(LLVMTargetMachine &TM, PassManagerBase &PM)
: AMDGPUPassConfig(TM, PM) {
// It is necessary to know the register usage of the entire call graph. We
// allow calls without EnableAMDGPUFunctionCalls if they are marked
// noinline, so this is always required.
setRequiresCodeGenSCCOrder(true);
}
GCNTargetMachine &getGCNTargetMachine() const {
return getTM<GCNTargetMachine>();
}
ScheduleDAGInstrs *
createMachineScheduler(MachineSchedContext *C) const override;
bool addPreISel() override;
void addMachineSSAOptimization() override;
bool addILPOpts() override;
bool addInstSelector() override;
bool addIRTranslator() override;
bool addLegalizeMachineIR() override;
bool addRegBankSelect() override;
bool addGlobalInstructionSelect() override;
void addFastRegAlloc(FunctionPass *RegAllocPass) override;
void addOptimizedRegAlloc(FunctionPass *RegAllocPass) override;
void addPreRegAlloc() override;
void addPostRegAlloc() override;
void addPreSched2() override;
void addPreEmitPass() override;
};
} // end anonymous namespace
TargetIRAnalysis AMDGPUTargetMachine::getTargetIRAnalysis() {
return TargetIRAnalysis([this](const Function &F) {
return TargetTransformInfo(AMDGPUTTIImpl(this, F));
});
}
void AMDGPUPassConfig::addEarlyCSEOrGVNPass() {
if (getOptLevel() == CodeGenOpt::Aggressive)
addPass(createGVNPass());
else
addPass(createEarlyCSEPass());
}
void AMDGPUPassConfig::addStraightLineScalarOptimizationPasses() {
addPass(createSeparateConstOffsetFromGEPPass());
addPass(createSpeculativeExecutionPass());
// ReassociateGEPs exposes more opportunites for SLSR. See
// the example in reassociate-geps-and-slsr.ll.
addPass(createStraightLineStrengthReducePass());
// SeparateConstOffsetFromGEP and SLSR creates common expressions which GVN or
// EarlyCSE can reuse.
addEarlyCSEOrGVNPass();
// Run NaryReassociate after EarlyCSE/GVN to be more effective.
addPass(createNaryReassociatePass());
// NaryReassociate on GEPs creates redundant common expressions, so run
// EarlyCSE after it.
addPass(createEarlyCSEPass());
}
void AMDGPUPassConfig::addIRPasses() {
const AMDGPUTargetMachine &TM = getAMDGPUTargetMachine();
// There is no reason to run these.
disablePass(&StackMapLivenessID);
disablePass(&FuncletLayoutID);
disablePass(&PatchableFunctionID);
addPass(createAMDGPULowerIntrinsicsPass());
if (TM.getTargetTriple().getArch() == Triple::r600 ||
!EnableAMDGPUFunctionCalls) {
// Function calls are not supported, so make sure we inline everything.
addPass(createAMDGPUAlwaysInlinePass());
addPass(createAlwaysInlinerLegacyPass());
// We need to add the barrier noop pass, otherwise adding the function
// inlining pass will cause all of the PassConfigs passes to be run
// one function at a time, which means if we have a nodule with two
// functions, then we will generate code for the first function
// without ever running any passes on the second.
addPass(createBarrierNoopPass());
}
if (TM.getTargetTriple().getArch() == Triple::amdgcn) {
// TODO: May want to move later or split into an early and late one.
addPass(createAMDGPUCodeGenPreparePass());
}
// Handle uses of OpenCL image2d_t, image3d_t and sampler_t arguments.
addPass(createAMDGPUOpenCLImageTypeLoweringPass());
// Replace OpenCL enqueued block function pointers with global variables.
addPass(createAMDGPUOpenCLEnqueuedBlockLoweringPass());
if (TM.getOptLevel() > CodeGenOpt::None) {
addPass(createInferAddressSpacesPass());
addPass(createAMDGPUPromoteAlloca());
if (EnableSROA)
addPass(createSROAPass());
addStraightLineScalarOptimizationPasses();
if (EnableAMDGPUAliasAnalysis) {
addPass(createAMDGPUAAWrapperPass());
addPass(createExternalAAWrapperPass([](Pass &P, Function &,
AAResults &AAR) {
if (auto *WrapperPass = P.getAnalysisIfAvailable<AMDGPUAAWrapperPass>())
AAR.addAAResult(WrapperPass->getResult());
}));
}
}
TargetPassConfig::addIRPasses();
// EarlyCSE is not always strong enough to clean up what LSR produces. For
// example, GVN can combine
//
// %0 = add %a, %b
// %1 = add %b, %a
//
// and
//
// %0 = shl nsw %a, 2
// %1 = shl %a, 2
//
// but EarlyCSE can do neither of them.
if (getOptLevel() != CodeGenOpt::None)
addEarlyCSEOrGVNPass();
}
void AMDGPUPassConfig::addCodeGenPrepare() {
TargetPassConfig::addCodeGenPrepare();
if (EnableLoadStoreVectorizer)
addPass(createLoadStoreVectorizerPass());
}
bool AMDGPUPassConfig::addPreISel() {
addPass(createFlattenCFGPass());
return false;
}
bool AMDGPUPassConfig::addInstSelector() {
addPass(createAMDGPUISelDag(&getAMDGPUTargetMachine(), getOptLevel()));
return false;
}
bool AMDGPUPassConfig::addGCPasses() {
// Do nothing. GC is not supported.
return false;
}
//===----------------------------------------------------------------------===//
// R600 Pass Setup
//===----------------------------------------------------------------------===//
bool R600PassConfig::addPreISel() {
AMDGPUPassConfig::addPreISel();
if (EnableR600StructurizeCFG)
addPass(createStructurizeCFGPass());
return false;
}
bool R600PassConfig::addInstSelector() {
addPass(createR600ISelDag(&getAMDGPUTargetMachine(), getOptLevel()));
return false;
}
void R600PassConfig::addPreRegAlloc() {
addPass(createR600VectorRegMerger());
}
void R600PassConfig::addPreSched2() {
addPass(createR600EmitClauseMarkers(), false);
if (EnableR600IfConvert)
addPass(&IfConverterID, false);
addPass(createR600ClauseMergePass(), false);
}
void R600PassConfig::addPreEmitPass() {
addPass(createAMDGPUCFGStructurizerPass(), false);
addPass(createR600ExpandSpecialInstrsPass(), false);
addPass(&FinalizeMachineBundlesID, false);
addPass(createR600Packetizer(), false);
addPass(createR600ControlFlowFinalizer(), false);
}
TargetPassConfig *R600TargetMachine::createPassConfig(PassManagerBase &PM) {
return new R600PassConfig(*this, PM);
}
//===----------------------------------------------------------------------===//
// GCN Pass Setup
//===----------------------------------------------------------------------===//
ScheduleDAGInstrs *GCNPassConfig::createMachineScheduler(
MachineSchedContext *C) const {
const SISubtarget &ST = C->MF->getSubtarget<SISubtarget>();
if (ST.enableSIScheduler())
return createSIMachineScheduler(C);
return createGCNMaxOccupancyMachineScheduler(C);
}
bool GCNPassConfig::addPreISel() {
AMDGPUPassConfig::addPreISel();
// FIXME: We need to run a pass to propagate the attributes when calls are
// supported.
addPass(createAMDGPUAnnotateKernelFeaturesPass());
// Merge divergent exit nodes. StructurizeCFG won't recognize the multi-exit
// regions formed by them.
addPass(&AMDGPUUnifyDivergentExitNodesID);
if (!LateCFGStructurize) {
addPass(createStructurizeCFGPass(true)); // true -> SkipUniformRegions
}
addPass(createSinkingPass());
addPass(createAMDGPUAnnotateUniformValues());
if (!LateCFGStructurize) {
addPass(createSIAnnotateControlFlowPass());
}
return false;
}
void GCNPassConfig::addMachineSSAOptimization() {
TargetPassConfig::addMachineSSAOptimization();
// We want to fold operands after PeepholeOptimizer has run (or as part of
// it), because it will eliminate extra copies making it easier to fold the
// real source operand. We want to eliminate dead instructions after, so that
// we see fewer uses of the copies. We then need to clean up the dead
// instructions leftover after the operands are folded as well.
//
// XXX - Can we get away without running DeadMachineInstructionElim again?
addPass(&SIFoldOperandsID);
addPass(&DeadMachineInstructionElimID);
addPass(&SILoadStoreOptimizerID);
if (EnableSDWAPeephole) {
addPass(&SIPeepholeSDWAID);
addPass(&MachineLICMID);
addPass(&MachineCSEID);
addPass(&SIFoldOperandsID);
addPass(&DeadMachineInstructionElimID);
}
addPass(createSIShrinkInstructionsPass());
}
bool GCNPassConfig::addILPOpts() {
if (EnableEarlyIfConversion)
addPass(&EarlyIfConverterID);
TargetPassConfig::addILPOpts();
return false;
}
bool GCNPassConfig::addInstSelector() {
AMDGPUPassConfig::addInstSelector();
addPass(createSILowerI1CopiesPass());
addPass(&SIFixSGPRCopiesID);
return false;
}
bool GCNPassConfig::addIRTranslator() {
addPass(new IRTranslator());
return false;
}
bool GCNPassConfig::addLegalizeMachineIR() {
addPass(new Legalizer());
return false;
}
bool GCNPassConfig::addRegBankSelect() {
addPass(new RegBankSelect());
return false;
}
bool GCNPassConfig::addGlobalInstructionSelect() {
addPass(new InstructionSelect());
return false;
}
void GCNPassConfig::addPreRegAlloc() {
if (LateCFGStructurize) {
addPass(createAMDGPUMachineCFGStructurizerPass());
}
addPass(createSIWholeQuadModePass());
}
void GCNPassConfig::addFastRegAlloc(FunctionPass *RegAllocPass) {
// FIXME: We have to disable the verifier here because of PHIElimination +
// TwoAddressInstructions disabling it.
// This must be run immediately after phi elimination and before
// TwoAddressInstructions, otherwise the processing of the tied operand of
// SI_ELSE will introduce a copy of the tied operand source after the else.
insertPass(&PHIEliminationID, &SILowerControlFlowID, false);
[AMDGPU] Add support for Whole Wavefront Mode Summary: Whole Wavefront Wode (WWM) is similar to WQM, except that all of the lanes are always enabled, regardless of control flow. This is required for implementing wavefront reductions in non-uniform control flow, where we need to use the inactive lanes to propagate intermediate results, so they need to be enabled. We need to propagate WWM to uses (unless they're explicitly marked as exact) so that they also propagate intermediate results correctly. We do the analysis and exec mask munging during the WQM pass, since there are interactions with WQM for things that require both WQM and WWM. For simplicity, WWM is entirely block-local -- blocks are never WWM on entry or exit of a block, and WWM is not propagated to the block level. This means that computations involving WWM cannot involve control flow, but we only ever plan to use WWM for a few limited purposes (none of which involve control flow) anyways. Shaders can ask for WWM using the @llvm.amdgcn.wwm intrinsic. There isn't yet a way to turn WWM off -- that will be added in a future change. Finally, it turns out that turning on inactive lanes causes a number of problems with register allocation. While the best long-term solution seems like teaching LLVM's register allocator about predication, for now we need to add some hacks to prevent ourselves from getting into trouble due to constraints that aren't currently expressed in LLVM. For the gory details, see the comments at the top of SIFixWWMLiveness.cpp. Reviewers: arsenm, nhaehnle, tpr Subscribers: kzhuravl, wdng, mgorny, yaxunl, dstuttard, t-tye, llvm-commits Differential Revision: https://reviews.llvm.org/D35524 llvm-svn: 310087
2017-08-05 02:36:52 +08:00
// This must be run after SILowerControlFlow, since it needs to use the
// machine-level CFG, but before register allocation.
insertPass(&SILowerControlFlowID, &SIFixWWMLivenessID, false);
TargetPassConfig::addFastRegAlloc(RegAllocPass);
}
void GCNPassConfig::addOptimizedRegAlloc(FunctionPass *RegAllocPass) {
insertPass(&MachineSchedulerID, &SIOptimizeExecMaskingPreRAID);
// This must be run immediately after phi elimination and before
// TwoAddressInstructions, otherwise the processing of the tied operand of
// SI_ELSE will introduce a copy of the tied operand source after the else.
insertPass(&PHIEliminationID, &SILowerControlFlowID, false);
[AMDGPU] Add support for Whole Wavefront Mode Summary: Whole Wavefront Wode (WWM) is similar to WQM, except that all of the lanes are always enabled, regardless of control flow. This is required for implementing wavefront reductions in non-uniform control flow, where we need to use the inactive lanes to propagate intermediate results, so they need to be enabled. We need to propagate WWM to uses (unless they're explicitly marked as exact) so that they also propagate intermediate results correctly. We do the analysis and exec mask munging during the WQM pass, since there are interactions with WQM for things that require both WQM and WWM. For simplicity, WWM is entirely block-local -- blocks are never WWM on entry or exit of a block, and WWM is not propagated to the block level. This means that computations involving WWM cannot involve control flow, but we only ever plan to use WWM for a few limited purposes (none of which involve control flow) anyways. Shaders can ask for WWM using the @llvm.amdgcn.wwm intrinsic. There isn't yet a way to turn WWM off -- that will be added in a future change. Finally, it turns out that turning on inactive lanes causes a number of problems with register allocation. While the best long-term solution seems like teaching LLVM's register allocator about predication, for now we need to add some hacks to prevent ourselves from getting into trouble due to constraints that aren't currently expressed in LLVM. For the gory details, see the comments at the top of SIFixWWMLiveness.cpp. Reviewers: arsenm, nhaehnle, tpr Subscribers: kzhuravl, wdng, mgorny, yaxunl, dstuttard, t-tye, llvm-commits Differential Revision: https://reviews.llvm.org/D35524 llvm-svn: 310087
2017-08-05 02:36:52 +08:00
// This must be run after SILowerControlFlow, since it needs to use the
// machine-level CFG, but before register allocation.
insertPass(&SILowerControlFlowID, &SIFixWWMLivenessID, false);
TargetPassConfig::addOptimizedRegAlloc(RegAllocPass);
}
void GCNPassConfig::addPostRegAlloc() {
addPass(&SIFixVGPRCopiesID);
addPass(&SIOptimizeExecMaskingID);
TargetPassConfig::addPostRegAlloc();
}
void GCNPassConfig::addPreSched2() {
}
void GCNPassConfig::addPreEmitPass() {
// The hazard recognizer that runs as part of the post-ra scheduler does not
2016-06-29 00:59:53 +08:00
// guarantee to be able handle all hazards correctly. This is because if there
// are multiple scheduling regions in a basic block, the regions are scheduled
// bottom up, so when we begin to schedule a region we don't know what
// instructions were emitted directly before it.
//
2016-06-29 00:59:53 +08:00
// Here we add a stand-alone hazard recognizer pass which can handle all
// cases.
addPass(&PostRAHazardRecognizerID);
if (EnableSIInsertWaitcntsPass)
addPass(createSIInsertWaitcntsPass());
else
addPass(createSIInsertWaitsPass());
addPass(createSIShrinkInstructionsPass());
addPass(&SIInsertSkipsPassID);
addPass(createSIMemoryLegalizerPass());
addPass(createSIDebuggerInsertNopsPass());
addPass(&BranchRelaxationPassID);
}
TargetPassConfig *GCNTargetMachine::createPassConfig(PassManagerBase &PM) {
return new GCNPassConfig(*this, PM);
}