forked from OSchip/llvm-project
834 lines
26 KiB
C++
834 lines
26 KiB
C++
//===-- AMDGPUPromoteAlloca.cpp - Promote Allocas -------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This pass eliminates allocas by either converting them into vectors or
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// by migrating them to local address space.
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//
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//===----------------------------------------------------------------------===//
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#include "AMDGPU.h"
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#include "AMDGPUSubtarget.h"
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#include "llvm/Analysis/ValueTracking.h"
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#include "llvm/IR/IRBuilder.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/MDBuilder.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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#define DEBUG_TYPE "amdgpu-promote-alloca"
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using namespace llvm;
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namespace {
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// FIXME: This can create globals so should be a module pass.
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class AMDGPUPromoteAlloca : public FunctionPass {
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private:
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const TargetMachine *TM;
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Module *Mod;
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const DataLayout *DL;
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MDNode *MaxWorkGroupSizeRange;
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// FIXME: This should be per-kernel.
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uint32_t LocalMemLimit;
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uint32_t CurrentLocalMemUsage;
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bool IsAMDGCN;
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bool IsAMDHSA;
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std::pair<Value *, Value *> getLocalSizeYZ(IRBuilder<> &Builder);
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Value *getWorkitemID(IRBuilder<> &Builder, unsigned N);
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/// BaseAlloca is the alloca root the search started from.
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/// Val may be that alloca or a recursive user of it.
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bool collectUsesWithPtrTypes(Value *BaseAlloca,
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Value *Val,
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std::vector<Value*> &WorkList) const;
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/// Val is a derived pointer from Alloca. OpIdx0/OpIdx1 are the operand
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/// indices to an instruction with 2 pointer inputs (e.g. select, icmp).
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/// Returns true if both operands are derived from the same alloca. Val should
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/// be the same value as one of the input operands of UseInst.
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bool binaryOpIsDerivedFromSameAlloca(Value *Alloca, Value *Val,
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Instruction *UseInst,
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int OpIdx0, int OpIdx1) const;
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public:
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static char ID;
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AMDGPUPromoteAlloca(const TargetMachine *TM_ = nullptr) :
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FunctionPass(ID),
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TM(TM_),
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Mod(nullptr),
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DL(nullptr),
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MaxWorkGroupSizeRange(nullptr),
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LocalMemLimit(0),
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CurrentLocalMemUsage(0),
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IsAMDGCN(false),
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IsAMDHSA(false) { }
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bool doInitialization(Module &M) override;
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bool runOnFunction(Function &F) override;
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StringRef getPassName() const override { return "AMDGPU Promote Alloca"; }
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void handleAlloca(AllocaInst &I);
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void getAnalysisUsage(AnalysisUsage &AU) const override {
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AU.setPreservesCFG();
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FunctionPass::getAnalysisUsage(AU);
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}
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};
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} // End anonymous namespace
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char AMDGPUPromoteAlloca::ID = 0;
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INITIALIZE_TM_PASS(AMDGPUPromoteAlloca, DEBUG_TYPE,
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"AMDGPU promote alloca to vector or LDS", false, false)
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char &llvm::AMDGPUPromoteAllocaID = AMDGPUPromoteAlloca::ID;
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bool AMDGPUPromoteAlloca::doInitialization(Module &M) {
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if (!TM)
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return false;
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Mod = &M;
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DL = &Mod->getDataLayout();
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// The maximum workitem id.
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//
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// FIXME: Should get as subtarget property. Usually runtime enforced max is
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// 256.
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MDBuilder MDB(Mod->getContext());
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MaxWorkGroupSizeRange = MDB.createRange(APInt(32, 0), APInt(32, 2048));
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const Triple &TT = TM->getTargetTriple();
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IsAMDGCN = TT.getArch() == Triple::amdgcn;
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IsAMDHSA = TT.getOS() == Triple::AMDHSA;
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return false;
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}
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bool AMDGPUPromoteAlloca::runOnFunction(Function &F) {
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if (!TM || skipFunction(F))
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return false;
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const AMDGPUSubtarget &ST = TM->getSubtarget<AMDGPUSubtarget>(F);
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if (!ST.isPromoteAllocaEnabled())
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return false;
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FunctionType *FTy = F.getFunctionType();
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// If the function has any arguments in the local address space, then it's
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// possible these arguments require the entire local memory space, so
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// we cannot use local memory in the pass.
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for (Type *ParamTy : FTy->params()) {
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PointerType *PtrTy = dyn_cast<PointerType>(ParamTy);
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if (PtrTy && PtrTy->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS) {
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LocalMemLimit = 0;
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DEBUG(dbgs() << "Function has local memory argument. Promoting to "
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"local memory disabled.\n");
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return false;
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}
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}
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LocalMemLimit = ST.getLocalMemorySize();
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if (LocalMemLimit == 0)
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return false;
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const DataLayout &DL = Mod->getDataLayout();
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// Check how much local memory is being used by global objects
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CurrentLocalMemUsage = 0;
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for (GlobalVariable &GV : Mod->globals()) {
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if (GV.getType()->getAddressSpace() != AMDGPUAS::LOCAL_ADDRESS)
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continue;
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for (const User *U : GV.users()) {
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const Instruction *Use = dyn_cast<Instruction>(U);
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if (!Use)
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continue;
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if (Use->getParent()->getParent() == &F) {
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unsigned Align = GV.getAlignment();
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if (Align == 0)
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Align = DL.getABITypeAlignment(GV.getValueType());
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// FIXME: Try to account for padding here. The padding is currently
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// determined from the inverse order of uses in the function. I'm not
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// sure if the use list order is in any way connected to this, so the
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// total reported size is likely incorrect.
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uint64_t AllocSize = DL.getTypeAllocSize(GV.getValueType());
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CurrentLocalMemUsage = alignTo(CurrentLocalMemUsage, Align);
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CurrentLocalMemUsage += AllocSize;
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break;
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}
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}
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}
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unsigned MaxOccupancy = ST.getOccupancyWithLocalMemSize(CurrentLocalMemUsage);
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// Restrict local memory usage so that we don't drastically reduce occupancy,
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// unless it is already significantly reduced.
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// TODO: Have some sort of hint or other heuristics to guess occupancy based
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// on other factors..
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unsigned OccupancyHint = ST.getWavesPerEU(F).second;
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if (OccupancyHint == 0)
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OccupancyHint = 7;
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// Clamp to max value.
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OccupancyHint = std::min(OccupancyHint, ST.getMaxWavesPerEU());
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// Check the hint but ignore it if it's obviously wrong from the existing LDS
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// usage.
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MaxOccupancy = std::min(OccupancyHint, MaxOccupancy);
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// Round up to the next tier of usage.
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unsigned MaxSizeWithWaveCount
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= ST.getMaxLocalMemSizeWithWaveCount(MaxOccupancy);
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// Program is possibly broken by using more local mem than available.
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if (CurrentLocalMemUsage > MaxSizeWithWaveCount)
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return false;
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LocalMemLimit = MaxSizeWithWaveCount;
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DEBUG(
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dbgs() << F.getName() << " uses " << CurrentLocalMemUsage << " bytes of LDS\n"
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<< " Rounding size to " << MaxSizeWithWaveCount
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<< " with a maximum occupancy of " << MaxOccupancy << '\n'
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<< " and " << (LocalMemLimit - CurrentLocalMemUsage)
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<< " available for promotion\n"
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);
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BasicBlock &EntryBB = *F.begin();
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for (auto I = EntryBB.begin(), E = EntryBB.end(); I != E; ) {
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AllocaInst *AI = dyn_cast<AllocaInst>(I);
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++I;
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if (AI)
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handleAlloca(*AI);
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}
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return true;
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}
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std::pair<Value *, Value *>
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AMDGPUPromoteAlloca::getLocalSizeYZ(IRBuilder<> &Builder) {
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if (!IsAMDHSA) {
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Function *LocalSizeYFn
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= Intrinsic::getDeclaration(Mod, Intrinsic::r600_read_local_size_y);
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Function *LocalSizeZFn
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= Intrinsic::getDeclaration(Mod, Intrinsic::r600_read_local_size_z);
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CallInst *LocalSizeY = Builder.CreateCall(LocalSizeYFn, {});
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CallInst *LocalSizeZ = Builder.CreateCall(LocalSizeZFn, {});
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LocalSizeY->setMetadata(LLVMContext::MD_range, MaxWorkGroupSizeRange);
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LocalSizeZ->setMetadata(LLVMContext::MD_range, MaxWorkGroupSizeRange);
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return std::make_pair(LocalSizeY, LocalSizeZ);
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}
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// We must read the size out of the dispatch pointer.
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assert(IsAMDGCN);
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// We are indexing into this struct, and want to extract the workgroup_size_*
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// fields.
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//
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// typedef struct hsa_kernel_dispatch_packet_s {
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// uint16_t header;
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// uint16_t setup;
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// uint16_t workgroup_size_x ;
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// uint16_t workgroup_size_y;
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// uint16_t workgroup_size_z;
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// uint16_t reserved0;
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// uint32_t grid_size_x ;
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// uint32_t grid_size_y ;
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// uint32_t grid_size_z;
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//
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// uint32_t private_segment_size;
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// uint32_t group_segment_size;
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// uint64_t kernel_object;
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//
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// #ifdef HSA_LARGE_MODEL
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// void *kernarg_address;
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// #elif defined HSA_LITTLE_ENDIAN
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// void *kernarg_address;
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// uint32_t reserved1;
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// #else
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// uint32_t reserved1;
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// void *kernarg_address;
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// #endif
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// uint64_t reserved2;
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// hsa_signal_t completion_signal; // uint64_t wrapper
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// } hsa_kernel_dispatch_packet_t
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//
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Function *DispatchPtrFn
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= Intrinsic::getDeclaration(Mod, Intrinsic::amdgcn_dispatch_ptr);
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CallInst *DispatchPtr = Builder.CreateCall(DispatchPtrFn, {});
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DispatchPtr->addAttribute(AttributeSet::ReturnIndex, Attribute::NoAlias);
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DispatchPtr->addAttribute(AttributeSet::ReturnIndex, Attribute::NonNull);
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// Size of the dispatch packet struct.
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DispatchPtr->addDereferenceableAttr(AttributeSet::ReturnIndex, 64);
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Type *I32Ty = Type::getInt32Ty(Mod->getContext());
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Value *CastDispatchPtr = Builder.CreateBitCast(
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DispatchPtr, PointerType::get(I32Ty, AMDGPUAS::CONSTANT_ADDRESS));
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// We could do a single 64-bit load here, but it's likely that the basic
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// 32-bit and extract sequence is already present, and it is probably easier
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// to CSE this. The loads should be mergable later anyway.
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Value *GEPXY = Builder.CreateConstInBoundsGEP1_64(CastDispatchPtr, 1);
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LoadInst *LoadXY = Builder.CreateAlignedLoad(GEPXY, 4);
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Value *GEPZU = Builder.CreateConstInBoundsGEP1_64(CastDispatchPtr, 2);
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LoadInst *LoadZU = Builder.CreateAlignedLoad(GEPZU, 4);
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MDNode *MD = llvm::MDNode::get(Mod->getContext(), None);
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LoadXY->setMetadata(LLVMContext::MD_invariant_load, MD);
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LoadZU->setMetadata(LLVMContext::MD_invariant_load, MD);
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LoadZU->setMetadata(LLVMContext::MD_range, MaxWorkGroupSizeRange);
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// Extract y component. Upper half of LoadZU should be zero already.
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Value *Y = Builder.CreateLShr(LoadXY, 16);
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return std::make_pair(Y, LoadZU);
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}
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Value *AMDGPUPromoteAlloca::getWorkitemID(IRBuilder<> &Builder, unsigned N) {
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Intrinsic::ID IntrID = Intrinsic::ID::not_intrinsic;
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switch (N) {
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case 0:
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IntrID = IsAMDGCN ? Intrinsic::amdgcn_workitem_id_x
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: Intrinsic::r600_read_tidig_x;
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break;
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case 1:
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IntrID = IsAMDGCN ? Intrinsic::amdgcn_workitem_id_y
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: Intrinsic::r600_read_tidig_y;
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break;
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case 2:
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IntrID = IsAMDGCN ? Intrinsic::amdgcn_workitem_id_z
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: Intrinsic::r600_read_tidig_z;
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break;
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default:
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llvm_unreachable("invalid dimension");
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}
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Function *WorkitemIdFn = Intrinsic::getDeclaration(Mod, IntrID);
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CallInst *CI = Builder.CreateCall(WorkitemIdFn);
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CI->setMetadata(LLVMContext::MD_range, MaxWorkGroupSizeRange);
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return CI;
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}
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static VectorType *arrayTypeToVecType(Type *ArrayTy) {
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return VectorType::get(ArrayTy->getArrayElementType(),
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ArrayTy->getArrayNumElements());
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}
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static Value *
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calculateVectorIndex(Value *Ptr,
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const std::map<GetElementPtrInst *, Value *> &GEPIdx) {
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GetElementPtrInst *GEP = cast<GetElementPtrInst>(Ptr);
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auto I = GEPIdx.find(GEP);
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return I == GEPIdx.end() ? nullptr : I->second;
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}
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static Value* GEPToVectorIndex(GetElementPtrInst *GEP) {
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// FIXME we only support simple cases
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if (GEP->getNumOperands() != 3)
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return nullptr;
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ConstantInt *I0 = dyn_cast<ConstantInt>(GEP->getOperand(1));
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if (!I0 || !I0->isZero())
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return nullptr;
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return GEP->getOperand(2);
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}
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// Not an instruction handled below to turn into a vector.
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//
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// TODO: Check isTriviallyVectorizable for calls and handle other
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// instructions.
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static bool canVectorizeInst(Instruction *Inst, User *User) {
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switch (Inst->getOpcode()) {
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case Instruction::Load:
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case Instruction::BitCast:
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case Instruction::AddrSpaceCast:
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return true;
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case Instruction::Store: {
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// Must be the stored pointer operand, not a stored value.
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StoreInst *SI = cast<StoreInst>(Inst);
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return SI->getPointerOperand() == User;
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}
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default:
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return false;
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}
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}
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static bool tryPromoteAllocaToVector(AllocaInst *Alloca) {
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ArrayType *AllocaTy = dyn_cast<ArrayType>(Alloca->getAllocatedType());
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DEBUG(dbgs() << "Alloca candidate for vectorization\n");
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// FIXME: There is no reason why we can't support larger arrays, we
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// are just being conservative for now.
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if (!AllocaTy ||
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AllocaTy->getElementType()->isVectorTy() ||
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AllocaTy->getNumElements() > 4 ||
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AllocaTy->getNumElements() < 2) {
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DEBUG(dbgs() << " Cannot convert type to vector\n");
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return false;
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}
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std::map<GetElementPtrInst*, Value*> GEPVectorIdx;
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std::vector<Value*> WorkList;
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for (User *AllocaUser : Alloca->users()) {
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GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(AllocaUser);
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if (!GEP) {
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if (!canVectorizeInst(cast<Instruction>(AllocaUser), Alloca))
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return false;
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WorkList.push_back(AllocaUser);
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continue;
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}
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Value *Index = GEPToVectorIndex(GEP);
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// If we can't compute a vector index from this GEP, then we can't
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// promote this alloca to vector.
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if (!Index) {
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DEBUG(dbgs() << " Cannot compute vector index for GEP " << *GEP << '\n');
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return false;
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}
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GEPVectorIdx[GEP] = Index;
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for (User *GEPUser : AllocaUser->users()) {
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if (!canVectorizeInst(cast<Instruction>(GEPUser), AllocaUser))
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return false;
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WorkList.push_back(GEPUser);
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}
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}
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VectorType *VectorTy = arrayTypeToVecType(AllocaTy);
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DEBUG(dbgs() << " Converting alloca to vector "
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<< *AllocaTy << " -> " << *VectorTy << '\n');
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for (Value *V : WorkList) {
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Instruction *Inst = cast<Instruction>(V);
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IRBuilder<> Builder(Inst);
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switch (Inst->getOpcode()) {
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case Instruction::Load: {
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Type *VecPtrTy = VectorTy->getPointerTo(AMDGPUAS::PRIVATE_ADDRESS);
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Value *Ptr = Inst->getOperand(0);
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Value *Index = calculateVectorIndex(Ptr, GEPVectorIdx);
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Value *BitCast = Builder.CreateBitCast(Alloca, VecPtrTy);
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Value *VecValue = Builder.CreateLoad(BitCast);
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Value *ExtractElement = Builder.CreateExtractElement(VecValue, Index);
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Inst->replaceAllUsesWith(ExtractElement);
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Inst->eraseFromParent();
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break;
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}
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case Instruction::Store: {
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Type *VecPtrTy = VectorTy->getPointerTo(AMDGPUAS::PRIVATE_ADDRESS);
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Value *Ptr = Inst->getOperand(1);
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Value *Index = calculateVectorIndex(Ptr, GEPVectorIdx);
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Value *BitCast = Builder.CreateBitCast(Alloca, VecPtrTy);
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Value *VecValue = Builder.CreateLoad(BitCast);
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Value *NewVecValue = Builder.CreateInsertElement(VecValue,
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Inst->getOperand(0),
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Index);
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Builder.CreateStore(NewVecValue, BitCast);
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Inst->eraseFromParent();
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break;
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}
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case Instruction::BitCast:
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case Instruction::AddrSpaceCast:
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break;
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default:
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llvm_unreachable("Inconsistency in instructions promotable to vector");
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}
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}
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return true;
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}
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static bool isCallPromotable(CallInst *CI) {
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IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
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if (!II)
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return false;
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switch (II->getIntrinsicID()) {
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case Intrinsic::memcpy:
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case Intrinsic::memmove:
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case Intrinsic::memset:
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case Intrinsic::lifetime_start:
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case Intrinsic::lifetime_end:
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case Intrinsic::invariant_start:
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case Intrinsic::invariant_end:
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case Intrinsic::invariant_group_barrier:
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case Intrinsic::objectsize:
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return true;
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default:
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return false;
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}
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}
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bool AMDGPUPromoteAlloca::binaryOpIsDerivedFromSameAlloca(Value *BaseAlloca,
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Value *Val,
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Instruction *Inst,
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int OpIdx0,
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int OpIdx1) const {
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// Figure out which operand is the one we might not be promoting.
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Value *OtherOp = Inst->getOperand(OpIdx0);
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if (Val == OtherOp)
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OtherOp = Inst->getOperand(OpIdx1);
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if (isa<ConstantPointerNull>(OtherOp))
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return true;
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Value *OtherObj = GetUnderlyingObject(OtherOp, *DL);
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if (!isa<AllocaInst>(OtherObj))
|
|
return false;
|
|
|
|
// TODO: We should be able to replace undefs with the right pointer type.
|
|
|
|
// TODO: If we know the other base object is another promotable
|
|
// alloca, not necessarily this alloca, we can do this. The
|
|
// important part is both must have the same address space at
|
|
// the end.
|
|
if (OtherObj != BaseAlloca) {
|
|
DEBUG(dbgs() << "Found a binary instruction with another alloca object\n");
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool AMDGPUPromoteAlloca::collectUsesWithPtrTypes(
|
|
Value *BaseAlloca,
|
|
Value *Val,
|
|
std::vector<Value*> &WorkList) const {
|
|
|
|
for (User *User : Val->users()) {
|
|
if (is_contained(WorkList, User))
|
|
continue;
|
|
|
|
if (CallInst *CI = dyn_cast<CallInst>(User)) {
|
|
if (!isCallPromotable(CI))
|
|
return false;
|
|
|
|
WorkList.push_back(User);
|
|
continue;
|
|
}
|
|
|
|
Instruction *UseInst = cast<Instruction>(User);
|
|
if (UseInst->getOpcode() == Instruction::PtrToInt)
|
|
return false;
|
|
|
|
if (LoadInst *LI = dyn_cast<LoadInst>(UseInst)) {
|
|
if (LI->isVolatile())
|
|
return false;
|
|
|
|
continue;
|
|
}
|
|
|
|
if (StoreInst *SI = dyn_cast<StoreInst>(UseInst)) {
|
|
if (SI->isVolatile())
|
|
return false;
|
|
|
|
// Reject if the stored value is not the pointer operand.
|
|
if (SI->getPointerOperand() != Val)
|
|
return false;
|
|
} else if (AtomicRMWInst *RMW = dyn_cast<AtomicRMWInst>(UseInst)) {
|
|
if (RMW->isVolatile())
|
|
return false;
|
|
} else if (AtomicCmpXchgInst *CAS = dyn_cast<AtomicCmpXchgInst>(UseInst)) {
|
|
if (CAS->isVolatile())
|
|
return false;
|
|
}
|
|
|
|
// Only promote a select if we know that the other select operand
|
|
// is from another pointer that will also be promoted.
|
|
if (ICmpInst *ICmp = dyn_cast<ICmpInst>(UseInst)) {
|
|
if (!binaryOpIsDerivedFromSameAlloca(BaseAlloca, Val, ICmp, 0, 1))
|
|
return false;
|
|
|
|
// May need to rewrite constant operands.
|
|
WorkList.push_back(ICmp);
|
|
}
|
|
|
|
if (!User->getType()->isPointerTy())
|
|
continue;
|
|
|
|
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(UseInst)) {
|
|
// Be conservative if an address could be computed outside the bounds of
|
|
// the alloca.
|
|
if (!GEP->isInBounds())
|
|
return false;
|
|
}
|
|
|
|
// Only promote a select if we know that the other select operand is from
|
|
// another pointer that will also be promoted.
|
|
if (SelectInst *SI = dyn_cast<SelectInst>(UseInst)) {
|
|
if (!binaryOpIsDerivedFromSameAlloca(BaseAlloca, Val, SI, 1, 2))
|
|
return false;
|
|
}
|
|
|
|
// Repeat for phis.
|
|
if (PHINode *Phi = dyn_cast<PHINode>(UseInst)) {
|
|
// TODO: Handle more complex cases. We should be able to replace loops
|
|
// over arrays.
|
|
switch (Phi->getNumIncomingValues()) {
|
|
case 1:
|
|
break;
|
|
case 2:
|
|
if (!binaryOpIsDerivedFromSameAlloca(BaseAlloca, Val, Phi, 0, 1))
|
|
return false;
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
WorkList.push_back(User);
|
|
if (!collectUsesWithPtrTypes(BaseAlloca, User, WorkList))
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
// FIXME: Should try to pick the most likely to be profitable allocas first.
|
|
void AMDGPUPromoteAlloca::handleAlloca(AllocaInst &I) {
|
|
// Array allocations are probably not worth handling, since an allocation of
|
|
// the array type is the canonical form.
|
|
if (!I.isStaticAlloca() || I.isArrayAllocation())
|
|
return;
|
|
|
|
IRBuilder<> Builder(&I);
|
|
|
|
// First try to replace the alloca with a vector
|
|
Type *AllocaTy = I.getAllocatedType();
|
|
|
|
DEBUG(dbgs() << "Trying to promote " << I << '\n');
|
|
|
|
if (tryPromoteAllocaToVector(&I)) {
|
|
DEBUG(dbgs() << " alloca is not a candidate for vectorization.\n");
|
|
return;
|
|
}
|
|
|
|
const Function &ContainingFunction = *I.getParent()->getParent();
|
|
|
|
// Don't promote the alloca to LDS for shader calling conventions as the work
|
|
// item ID intrinsics are not supported for these calling conventions.
|
|
// Furthermore not all LDS is available for some of the stages.
|
|
if (AMDGPU::isShader(ContainingFunction.getCallingConv()))
|
|
return;
|
|
|
|
const AMDGPUSubtarget &ST =
|
|
TM->getSubtarget<AMDGPUSubtarget>(ContainingFunction);
|
|
// FIXME: We should also try to get this value from the reqd_work_group_size
|
|
// function attribute if it is available.
|
|
unsigned WorkGroupSize = ST.getFlatWorkGroupSizes(ContainingFunction).second;
|
|
|
|
const DataLayout &DL = Mod->getDataLayout();
|
|
|
|
unsigned Align = I.getAlignment();
|
|
if (Align == 0)
|
|
Align = DL.getABITypeAlignment(I.getAllocatedType());
|
|
|
|
// FIXME: This computed padding is likely wrong since it depends on inverse
|
|
// usage order.
|
|
//
|
|
// FIXME: It is also possible that if we're allowed to use all of the memory
|
|
// could could end up using more than the maximum due to alignment padding.
|
|
|
|
uint32_t NewSize = alignTo(CurrentLocalMemUsage, Align);
|
|
uint32_t AllocSize = WorkGroupSize * DL.getTypeAllocSize(AllocaTy);
|
|
NewSize += AllocSize;
|
|
|
|
if (NewSize > LocalMemLimit) {
|
|
DEBUG(dbgs() << " " << AllocSize
|
|
<< " bytes of local memory not available to promote\n");
|
|
return;
|
|
}
|
|
|
|
CurrentLocalMemUsage = NewSize;
|
|
|
|
std::vector<Value*> WorkList;
|
|
|
|
if (!collectUsesWithPtrTypes(&I, &I, WorkList)) {
|
|
DEBUG(dbgs() << " Do not know how to convert all uses\n");
|
|
return;
|
|
}
|
|
|
|
DEBUG(dbgs() << "Promoting alloca to local memory\n");
|
|
|
|
Function *F = I.getParent()->getParent();
|
|
|
|
Type *GVTy = ArrayType::get(I.getAllocatedType(), WorkGroupSize);
|
|
GlobalVariable *GV = new GlobalVariable(
|
|
*Mod, GVTy, false, GlobalValue::InternalLinkage,
|
|
UndefValue::get(GVTy),
|
|
Twine(F->getName()) + Twine('.') + I.getName(),
|
|
nullptr,
|
|
GlobalVariable::NotThreadLocal,
|
|
AMDGPUAS::LOCAL_ADDRESS);
|
|
GV->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
|
|
GV->setAlignment(I.getAlignment());
|
|
|
|
Value *TCntY, *TCntZ;
|
|
|
|
std::tie(TCntY, TCntZ) = getLocalSizeYZ(Builder);
|
|
Value *TIdX = getWorkitemID(Builder, 0);
|
|
Value *TIdY = getWorkitemID(Builder, 1);
|
|
Value *TIdZ = getWorkitemID(Builder, 2);
|
|
|
|
Value *Tmp0 = Builder.CreateMul(TCntY, TCntZ, "", true, true);
|
|
Tmp0 = Builder.CreateMul(Tmp0, TIdX);
|
|
Value *Tmp1 = Builder.CreateMul(TIdY, TCntZ, "", true, true);
|
|
Value *TID = Builder.CreateAdd(Tmp0, Tmp1);
|
|
TID = Builder.CreateAdd(TID, TIdZ);
|
|
|
|
Value *Indices[] = {
|
|
Constant::getNullValue(Type::getInt32Ty(Mod->getContext())),
|
|
TID
|
|
};
|
|
|
|
Value *Offset = Builder.CreateInBoundsGEP(GVTy, GV, Indices);
|
|
I.mutateType(Offset->getType());
|
|
I.replaceAllUsesWith(Offset);
|
|
I.eraseFromParent();
|
|
|
|
for (Value *V : WorkList) {
|
|
CallInst *Call = dyn_cast<CallInst>(V);
|
|
if (!Call) {
|
|
if (ICmpInst *CI = dyn_cast<ICmpInst>(V)) {
|
|
Value *Src0 = CI->getOperand(0);
|
|
Type *EltTy = Src0->getType()->getPointerElementType();
|
|
PointerType *NewTy = PointerType::get(EltTy, AMDGPUAS::LOCAL_ADDRESS);
|
|
|
|
if (isa<ConstantPointerNull>(CI->getOperand(0)))
|
|
CI->setOperand(0, ConstantPointerNull::get(NewTy));
|
|
|
|
if (isa<ConstantPointerNull>(CI->getOperand(1)))
|
|
CI->setOperand(1, ConstantPointerNull::get(NewTy));
|
|
|
|
continue;
|
|
}
|
|
|
|
// The operand's value should be corrected on its own.
|
|
if (isa<AddrSpaceCastInst>(V))
|
|
continue;
|
|
|
|
Type *EltTy = V->getType()->getPointerElementType();
|
|
PointerType *NewTy = PointerType::get(EltTy, AMDGPUAS::LOCAL_ADDRESS);
|
|
|
|
// FIXME: It doesn't really make sense to try to do this for all
|
|
// instructions.
|
|
V->mutateType(NewTy);
|
|
|
|
// Adjust the types of any constant operands.
|
|
if (SelectInst *SI = dyn_cast<SelectInst>(V)) {
|
|
if (isa<ConstantPointerNull>(SI->getOperand(1)))
|
|
SI->setOperand(1, ConstantPointerNull::get(NewTy));
|
|
|
|
if (isa<ConstantPointerNull>(SI->getOperand(2)))
|
|
SI->setOperand(2, ConstantPointerNull::get(NewTy));
|
|
} else if (PHINode *Phi = dyn_cast<PHINode>(V)) {
|
|
for (unsigned I = 0, E = Phi->getNumIncomingValues(); I != E; ++I) {
|
|
if (isa<ConstantPointerNull>(Phi->getIncomingValue(I)))
|
|
Phi->setIncomingValue(I, ConstantPointerNull::get(NewTy));
|
|
}
|
|
}
|
|
|
|
continue;
|
|
}
|
|
|
|
IntrinsicInst *Intr = cast<IntrinsicInst>(Call);
|
|
Builder.SetInsertPoint(Intr);
|
|
switch (Intr->getIntrinsicID()) {
|
|
case Intrinsic::lifetime_start:
|
|
case Intrinsic::lifetime_end:
|
|
// These intrinsics are for address space 0 only
|
|
Intr->eraseFromParent();
|
|
continue;
|
|
case Intrinsic::memcpy: {
|
|
MemCpyInst *MemCpy = cast<MemCpyInst>(Intr);
|
|
Builder.CreateMemCpy(MemCpy->getRawDest(), MemCpy->getRawSource(),
|
|
MemCpy->getLength(), MemCpy->getAlignment(),
|
|
MemCpy->isVolatile());
|
|
Intr->eraseFromParent();
|
|
continue;
|
|
}
|
|
case Intrinsic::memmove: {
|
|
MemMoveInst *MemMove = cast<MemMoveInst>(Intr);
|
|
Builder.CreateMemMove(MemMove->getRawDest(), MemMove->getRawSource(),
|
|
MemMove->getLength(), MemMove->getAlignment(),
|
|
MemMove->isVolatile());
|
|
Intr->eraseFromParent();
|
|
continue;
|
|
}
|
|
case Intrinsic::memset: {
|
|
MemSetInst *MemSet = cast<MemSetInst>(Intr);
|
|
Builder.CreateMemSet(MemSet->getRawDest(), MemSet->getValue(),
|
|
MemSet->getLength(), MemSet->getAlignment(),
|
|
MemSet->isVolatile());
|
|
Intr->eraseFromParent();
|
|
continue;
|
|
}
|
|
case Intrinsic::invariant_start:
|
|
case Intrinsic::invariant_end:
|
|
case Intrinsic::invariant_group_barrier:
|
|
Intr->eraseFromParent();
|
|
// FIXME: I think the invariant marker should still theoretically apply,
|
|
// but the intrinsics need to be changed to accept pointers with any
|
|
// address space.
|
|
continue;
|
|
case Intrinsic::objectsize: {
|
|
Value *Src = Intr->getOperand(0);
|
|
Type *SrcTy = Src->getType()->getPointerElementType();
|
|
Function *ObjectSize = Intrinsic::getDeclaration(Mod,
|
|
Intrinsic::objectsize,
|
|
{ Intr->getType(), PointerType::get(SrcTy, AMDGPUAS::LOCAL_ADDRESS) }
|
|
);
|
|
|
|
CallInst *NewCall
|
|
= Builder.CreateCall(ObjectSize, { Src, Intr->getOperand(1) });
|
|
Intr->replaceAllUsesWith(NewCall);
|
|
Intr->eraseFromParent();
|
|
continue;
|
|
}
|
|
default:
|
|
Intr->dump();
|
|
llvm_unreachable("Don't know how to promote alloca intrinsic use.");
|
|
}
|
|
}
|
|
}
|
|
|
|
FunctionPass *llvm::createAMDGPUPromoteAlloca(const TargetMachine *TM) {
|
|
return new AMDGPUPromoteAlloca(TM);
|
|
}
|