Files
archived-llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp
Matt Arsenault a7474fd041 AMDGPU: Move SIFixSGPRLiveRanges to be a regalloc pass
Replace LiveInterval usage with LiveVariables. LiveIntervals
computes far more information than is needed for this pass
which just needs to find if an SGPR is live out of the
defining block.

LiveIntervals are not usually available that early, requiring
computing them twice which is very expensive. The extra run of
LiveIntervals/LiveVariables/SlotIndexes was costing in total
about 5% of compile time.

Continuing to use LiveIntervals is problematic. It seems
there is an option (early-live-intervals) to run the analysis
about where it should go to avoid recomputing LiveVariables,
but it seems to be completely broken with subreg liveness
enabled. There are also problems from trying to recompute
LiveIntervals since this seems to undo LiveVariables
and clearing kill flags, causing TwoAddressInstructions
to make bad decisions.

Insert the pass right after live variables and preserve it.
The tricky case to worry about might be phis since
LiveVariables doesn't count a register as live out if
in the successor block it is only used in a phi,
but I don't think this is a concern right now
because SIFixSGPRCopies replaces SGPR phis.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249087 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-01 22:10:03 +00:00

332 lines
11 KiB
C++

//===-- 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 "AMDGPUHSATargetObjectFile.h"
#include "AMDGPU.h"
#include "AMDGPUTargetTransformInfo.h"
#include "R600ISelLowering.h"
#include "R600InstrInfo.h"
#include "R600MachineScheduler.h"
#include "SIISelLowering.h"
#include "SIInstrInfo.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/CodeGen/MachineFunctionAnalysis.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/Verifier.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_os_ostream.h"
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/Scalar.h"
#include <llvm/CodeGen/Passes.h>
using namespace llvm;
extern "C" void LLVMInitializeAMDGPUTarget() {
// Register the target
RegisterTargetMachine<R600TargetMachine> X(TheAMDGPUTarget);
RegisterTargetMachine<GCNTargetMachine> Y(TheGCNTarget);
PassRegistry *PR = PassRegistry::getPassRegistry();
initializeSIFixSGPRLiveRangesPass(*PR);
}
static std::unique_ptr<TargetLoweringObjectFile> createTLOF(const Triple &TT) {
if (TT.getOS() == Triple::AMDHSA)
return make_unique<AMDGPUHSATargetObjectFile>();
return make_unique<TargetLoweringObjectFileELF>();
}
static ScheduleDAGInstrs *createR600MachineScheduler(MachineSchedContext *C) {
return new ScheduleDAGMILive(C, make_unique<R600SchedStrategy>());
}
static MachineSchedRegistry
SchedCustomRegistry("r600", "Run R600's custom scheduler",
createR600MachineScheduler);
static std::string computeDataLayout(const Triple &TT) {
std::string Ret = "e-p:32:32";
if (TT.getArch() == Triple::amdgcn) {
// 32-bit private, local, and region pointers. 64-bit global and constant.
Ret += "-p1:64:64-p2:64:64-p3:32:32-p4:64:64-p5:32:32-p24:64:64";
}
Ret += "-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256"
"-v512:512-v1024:1024-v2048:2048-n32:64";
return Ret;
}
AMDGPUTargetMachine::AMDGPUTargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
TargetOptions Options, Reloc::Model RM,
CodeModel::Model CM,
CodeGenOpt::Level OptLevel)
: LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options, RM, CM,
OptLevel),
TLOF(createTLOF(getTargetTriple())), Subtarget(TT, CPU, FS, *this),
IntrinsicInfo() {
setRequiresStructuredCFG(true);
initAsmInfo();
}
AMDGPUTargetMachine::~AMDGPUTargetMachine() { }
//===----------------------------------------------------------------------===//
// R600 Target Machine (R600 -> Cayman)
//===----------------------------------------------------------------------===//
R600TargetMachine::R600TargetMachine(const Target &T, const Triple &TT,
StringRef FS, StringRef CPU,
TargetOptions Options, Reloc::Model RM,
CodeModel::Model CM, CodeGenOpt::Level OL)
: AMDGPUTargetMachine(T, TT, FS, CPU, Options, RM, CM, OL) {}
//===----------------------------------------------------------------------===//
// GCN Target Machine (SI+)
//===----------------------------------------------------------------------===//
GCNTargetMachine::GCNTargetMachine(const Target &T, const Triple &TT,
StringRef FS, StringRef CPU,
TargetOptions Options, Reloc::Model RM,
CodeModel::Model CM, CodeGenOpt::Level OL)
: AMDGPUTargetMachine(T, TT, FS, CPU, Options, RM, CM, OL) {}
//===----------------------------------------------------------------------===//
// AMDGPU Pass Setup
//===----------------------------------------------------------------------===//
namespace {
class AMDGPUPassConfig : public TargetPassConfig {
public:
AMDGPUPassConfig(TargetMachine *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 {
const AMDGPUSubtarget &ST = *getAMDGPUTargetMachine().getSubtargetImpl();
if (ST.getGeneration() <= AMDGPUSubtarget::NORTHERN_ISLANDS)
return createR600MachineScheduler(C);
return nullptr;
}
void addIRPasses() override;
void addCodeGenPrepare() override;
bool addPreISel() override;
bool addInstSelector() override;
bool addGCPasses() override;
};
class R600PassConfig : public AMDGPUPassConfig {
public:
R600PassConfig(TargetMachine *TM, PassManagerBase &PM)
: AMDGPUPassConfig(TM, PM) { }
bool addPreISel() override;
void addPreRegAlloc() override;
void addPreSched2() override;
void addPreEmitPass() override;
};
class GCNPassConfig : public AMDGPUPassConfig {
public:
GCNPassConfig(TargetMachine *TM, PassManagerBase &PM)
: AMDGPUPassConfig(TM, PM) { }
bool addPreISel() override;
bool addInstSelector() override;
void addFastRegAlloc(FunctionPass *RegAllocPass) override;
void addOptimizedRegAlloc(FunctionPass *RegAllocPass) override;
void addPreRegAlloc() override;
void addPostRegAlloc() override;
void addPreSched2() override;
void addPreEmitPass() override;
};
} // End of anonymous namespace
TargetIRAnalysis AMDGPUTargetMachine::getTargetIRAnalysis() {
return TargetIRAnalysis([this](const Function &F) {
return TargetTransformInfo(
AMDGPUTTIImpl(this, F.getParent()->getDataLayout()));
});
}
void AMDGPUPassConfig::addIRPasses() {
// Function calls are not supported, so make sure we inline everything.
addPass(createAMDGPUAlwaysInlinePass());
addPass(createAlwaysInlinerPass());
// 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());
// Handle uses of OpenCL image2d_t, image3d_t and sampler_t arguments.
addPass(createAMDGPUOpenCLImageTypeLoweringPass());
TargetPassConfig::addIRPasses();
}
void AMDGPUPassConfig::addCodeGenPrepare() {
const AMDGPUSubtarget &ST = *getAMDGPUTargetMachine().getSubtargetImpl();
if (ST.isPromoteAllocaEnabled()) {
addPass(createAMDGPUPromoteAlloca(ST));
addPass(createSROAPass());
}
TargetPassConfig::addCodeGenPrepare();
}
bool
AMDGPUPassConfig::addPreISel() {
const AMDGPUSubtarget &ST = *getAMDGPUTargetMachine().getSubtargetImpl();
addPass(createFlattenCFGPass());
if (ST.IsIRStructurizerEnabled())
addPass(createStructurizeCFGPass());
return false;
}
bool AMDGPUPassConfig::addInstSelector() {
addPass(createAMDGPUISelDag(getAMDGPUTargetMachine()));
return false;
}
bool AMDGPUPassConfig::addGCPasses() {
// Do nothing. GC is not supported.
return false;
}
//===----------------------------------------------------------------------===//
// R600 Pass Setup
//===----------------------------------------------------------------------===//
bool R600PassConfig::addPreISel() {
AMDGPUPassConfig::addPreISel();
addPass(createR600TextureIntrinsicsReplacer());
return false;
}
void R600PassConfig::addPreRegAlloc() {
addPass(createR600VectorRegMerger(*TM));
}
void R600PassConfig::addPreSched2() {
const AMDGPUSubtarget &ST = *getAMDGPUTargetMachine().getSubtargetImpl();
addPass(createR600EmitClauseMarkers(), false);
if (ST.isIfCvtEnabled())
addPass(&IfConverterID, false);
addPass(createR600ClauseMergePass(*TM), false);
}
void R600PassConfig::addPreEmitPass() {
addPass(createAMDGPUCFGStructurizerPass(), false);
addPass(createR600ExpandSpecialInstrsPass(*TM), false);
addPass(&FinalizeMachineBundlesID, false);
addPass(createR600Packetizer(*TM), false);
addPass(createR600ControlFlowFinalizer(*TM), false);
}
TargetPassConfig *R600TargetMachine::createPassConfig(PassManagerBase &PM) {
return new R600PassConfig(this, PM);
}
//===----------------------------------------------------------------------===//
// GCN Pass Setup
//===----------------------------------------------------------------------===//
bool GCNPassConfig::addPreISel() {
AMDGPUPassConfig::addPreISel();
addPass(createSinkingPass());
addPass(createSITypeRewriter());
addPass(createSIAnnotateControlFlowPass());
return false;
}
bool GCNPassConfig::addInstSelector() {
AMDGPUPassConfig::addInstSelector();
addPass(createSILowerI1CopiesPass());
addPass(createSIFixSGPRCopiesPass(*TM));
addPass(createSIFoldOperandsPass());
return false;
}
void GCNPassConfig::addPreRegAlloc() {
const AMDGPUSubtarget &ST = *getAMDGPUTargetMachine().getSubtargetImpl();
// This needs to be run directly before register allocation because
// earlier passes might recompute live intervals.
// TODO: handle CodeGenOpt::None; fast RA ignores spill weights set by the pass
if (getOptLevel() > CodeGenOpt::None) {
initializeSIFixControlFlowLiveIntervalsPass(*PassRegistry::getPassRegistry());
insertPass(&MachineSchedulerID, &SIFixControlFlowLiveIntervalsID);
}
if (getOptLevel() > CodeGenOpt::None && ST.loadStoreOptEnabled()) {
// Don't do this with no optimizations since it throws away debug info by
// merging nonadjacent loads.
// This should be run after scheduling, but before register allocation. It
// also need extra copies to the address operand to be eliminated.
initializeSILoadStoreOptimizerPass(*PassRegistry::getPassRegistry());
insertPass(&MachineSchedulerID, &SILoadStoreOptimizerID);
insertPass(&MachineSchedulerID, &RegisterCoalescerID);
}
addPass(createSIShrinkInstructionsPass(), false);
}
void GCNPassConfig::addFastRegAlloc(FunctionPass *RegAllocPass) {
addPass(&SIFixSGPRLiveRangesID);
TargetPassConfig::addFastRegAlloc(RegAllocPass);
}
void GCNPassConfig::addOptimizedRegAlloc(FunctionPass *RegAllocPass) {
// We want to run this after LiveVariables is computed to avoid computing them
// twice.
insertPass(&LiveVariablesID, &SIFixSGPRLiveRangesID);
TargetPassConfig::addOptimizedRegAlloc(RegAllocPass);
}
void GCNPassConfig::addPostRegAlloc() {
addPass(createSIPrepareScratchRegs(), false);
addPass(createSIShrinkInstructionsPass(), false);
}
void GCNPassConfig::addPreSched2() {
}
void GCNPassConfig::addPreEmitPass() {
addPass(createSIInsertWaits(*TM), false);
addPass(createSILowerControlFlowPass(*TM), false);
}
TargetPassConfig *GCNTargetMachine::createPassConfig(PassManagerBase &PM) {
return new GCNPassConfig(this, PM);
}