diff options
Diffstat (limited to 'contrib/llvm/lib/Target/R600/AMDILPeepholeOptimizer.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/R600/AMDILPeepholeOptimizer.cpp | 1215 |
1 files changed, 1215 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/R600/AMDILPeepholeOptimizer.cpp b/contrib/llvm/lib/Target/R600/AMDILPeepholeOptimizer.cpp new file mode 100644 index 0000000..3a28038 --- /dev/null +++ b/contrib/llvm/lib/Target/R600/AMDILPeepholeOptimizer.cpp @@ -0,0 +1,1215 @@ +//===-- AMDILPeepholeOptimizer.cpp - AMDGPU Peephole optimizations ---------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +/// \file +//==-----------------------------------------------------------------------===// + +#define DEBUG_TYPE "PeepholeOpt" +#ifdef DEBUG +#define DEBUGME (DebugFlag && isCurrentDebugType(DEBUG_TYPE)) +#else +#define DEBUGME 0 +#endif + +#include "AMDILDevices.h" +#include "AMDGPUInstrInfo.h" +#include "llvm/ADT/Statistic.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Twine.h" +#include "llvm/IR/Constants.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineFunctionAnalysis.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/Module.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/MathExtras.h" + +#include <sstream> + +#if 0 +STATISTIC(PointerAssignments, "Number of dynamic pointer " + "assigments discovered"); +STATISTIC(PointerSubtract, "Number of pointer subtractions discovered"); +#endif + +using namespace llvm; +// The Peephole optimization pass is used to do simple last minute optimizations +// that are required for correct code or to remove redundant functions +namespace { + +class OpaqueType; + +class LLVM_LIBRARY_VISIBILITY AMDGPUPeepholeOpt : public FunctionPass { +public: + TargetMachine &TM; + static char ID; + AMDGPUPeepholeOpt(TargetMachine &tm); + ~AMDGPUPeepholeOpt(); + const char *getPassName() const; + bool runOnFunction(Function &F); + bool doInitialization(Module &M); + bool doFinalization(Module &M); + void getAnalysisUsage(AnalysisUsage &AU) const; +protected: +private: + // Function to initiate all of the instruction level optimizations. + bool instLevelOptimizations(BasicBlock::iterator *inst); + // Quick check to see if we need to dump all of the pointers into the + // arena. If this is correct, then we set all pointers to exist in arena. This + // is a workaround for aliasing of pointers in a struct/union. + bool dumpAllIntoArena(Function &F); + // Because I don't want to invalidate any pointers while in the + // safeNestedForEachFunction. I push atomic conversions to a vector and handle + // it later. This function does the conversions if required. + void doAtomicConversionIfNeeded(Function &F); + // Because __amdil_is_constant cannot be properly evaluated if + // optimizations are disabled, the call's are placed in a vector + // and evaluated after the __amdil_image* functions are evaluated + // which should allow the __amdil_is_constant function to be + // evaluated correctly. + void doIsConstCallConversionIfNeeded(); + bool mChanged; + bool mDebug; + bool mConvertAtomics; + CodeGenOpt::Level optLevel; + // Run a series of tests to see if we can optimize a CALL instruction. + bool optimizeCallInst(BasicBlock::iterator *bbb); + // A peephole optimization to optimize bit extract sequences. + bool optimizeBitExtract(Instruction *inst); + // A peephole optimization to optimize bit insert sequences. + bool optimizeBitInsert(Instruction *inst); + bool setupBitInsert(Instruction *base, + Instruction *&src, + Constant *&mask, + Constant *&shift); + // Expand the bit field insert instruction on versions of OpenCL that + // don't support it. + bool expandBFI(CallInst *CI); + // Expand the bit field mask instruction on version of OpenCL that + // don't support it. + bool expandBFM(CallInst *CI); + // On 7XX and 8XX operations, we do not have 24 bit signed operations. So in + // this case we need to expand them. These functions check for 24bit functions + // and then expand. + bool isSigned24BitOps(CallInst *CI); + void expandSigned24BitOps(CallInst *CI); + // One optimization that can occur is that if the required workgroup size is + // specified then the result of get_local_size is known at compile time and + // can be returned accordingly. + bool isRWGLocalOpt(CallInst *CI); + // On northern island cards, the division is slightly less accurate than on + // previous generations, so we need to utilize a more accurate division. So we + // can translate the accurate divide to a normal divide on all other cards. + bool convertAccurateDivide(CallInst *CI); + void expandAccurateDivide(CallInst *CI); + // If the alignment is set incorrectly, it can produce really inefficient + // code. This checks for this scenario and fixes it if possible. + bool correctMisalignedMemOp(Instruction *inst); + + // If we are in no opt mode, then we need to make sure that + // local samplers are properly propagated as constant propagation + // doesn't occur and we need to know the value of kernel defined + // samplers at compile time. + bool propagateSamplerInst(CallInst *CI); + + // Helper functions + + // Group of functions that recursively calculate the size of a structure based + // on it's sub-types. + size_t getTypeSize(Type * const T, bool dereferencePtr = false); + size_t getTypeSize(StructType * const ST, bool dereferencePtr = false); + size_t getTypeSize(IntegerType * const IT, bool dereferencePtr = false); + size_t getTypeSize(FunctionType * const FT,bool dereferencePtr = false); + size_t getTypeSize(ArrayType * const AT, bool dereferencePtr = false); + size_t getTypeSize(VectorType * const VT, bool dereferencePtr = false); + size_t getTypeSize(PointerType * const PT, bool dereferencePtr = false); + size_t getTypeSize(OpaqueType * const OT, bool dereferencePtr = false); + + LLVMContext *mCTX; + Function *mF; + const AMDGPUSubtarget *mSTM; + SmallVector< std::pair<CallInst *, Function *>, 16> atomicFuncs; + SmallVector<CallInst *, 16> isConstVec; +}; // class AMDGPUPeepholeOpt + char AMDGPUPeepholeOpt::ID = 0; + +// A template function that has two levels of looping before calling the +// function with a pointer to the current iterator. +template<class InputIterator, class SecondIterator, class Function> +Function safeNestedForEach(InputIterator First, InputIterator Last, + SecondIterator S, Function F) { + for ( ; First != Last; ++First) { + SecondIterator sf, sl; + for (sf = First->begin(), sl = First->end(); + sf != sl; ) { + if (!F(&sf)) { + ++sf; + } + } + } + return F; +} + +} // anonymous namespace + +namespace llvm { + FunctionPass * + createAMDGPUPeepholeOpt(TargetMachine &tm) { + return new AMDGPUPeepholeOpt(tm); + } +} // llvm namespace + +AMDGPUPeepholeOpt::AMDGPUPeepholeOpt(TargetMachine &tm) + : FunctionPass(ID), TM(tm) { + mDebug = DEBUGME; + optLevel = TM.getOptLevel(); + +} + +AMDGPUPeepholeOpt::~AMDGPUPeepholeOpt() { +} + +const char * +AMDGPUPeepholeOpt::getPassName() const { + return "AMDGPU PeepHole Optimization Pass"; +} + +bool +containsPointerType(Type *Ty) { + if (!Ty) { + return false; + } + switch(Ty->getTypeID()) { + default: + return false; + case Type::StructTyID: { + const StructType *ST = dyn_cast<StructType>(Ty); + for (StructType::element_iterator stb = ST->element_begin(), + ste = ST->element_end(); stb != ste; ++stb) { + if (!containsPointerType(*stb)) { + continue; + } + return true; + } + break; + } + case Type::VectorTyID: + case Type::ArrayTyID: + return containsPointerType(dyn_cast<SequentialType>(Ty)->getElementType()); + case Type::PointerTyID: + return true; + }; + return false; +} + +bool +AMDGPUPeepholeOpt::dumpAllIntoArena(Function &F) { + bool dumpAll = false; + for (Function::const_arg_iterator cab = F.arg_begin(), + cae = F.arg_end(); cab != cae; ++cab) { + const Argument *arg = cab; + const PointerType *PT = dyn_cast<PointerType>(arg->getType()); + if (!PT) { + continue; + } + Type *DereferencedType = PT->getElementType(); + if (!dyn_cast<StructType>(DereferencedType) + ) { + continue; + } + if (!containsPointerType(DereferencedType)) { + continue; + } + // FIXME: Because a pointer inside of a struct/union may be aliased to + // another pointer we need to take the conservative approach and place all + // pointers into the arena until more advanced detection is implemented. + dumpAll = true; + } + return dumpAll; +} +void +AMDGPUPeepholeOpt::doIsConstCallConversionIfNeeded() { + if (isConstVec.empty()) { + return; + } + for (unsigned x = 0, y = isConstVec.size(); x < y; ++x) { + CallInst *CI = isConstVec[x]; + Constant *CV = dyn_cast<Constant>(CI->getOperand(0)); + Type *aType = Type::getInt32Ty(*mCTX); + Value *Val = (CV != NULL) ? ConstantInt::get(aType, 1) + : ConstantInt::get(aType, 0); + CI->replaceAllUsesWith(Val); + CI->eraseFromParent(); + } + isConstVec.clear(); +} +void +AMDGPUPeepholeOpt::doAtomicConversionIfNeeded(Function &F) { + // Don't do anything if we don't have any atomic operations. + if (atomicFuncs.empty()) { + return; + } + // Change the function name for the atomic if it is required + uint32_t size = atomicFuncs.size(); + for (uint32_t x = 0; x < size; ++x) { + atomicFuncs[x].first->setOperand( + atomicFuncs[x].first->getNumOperands()-1, + atomicFuncs[x].second); + + } + mChanged = true; + if (mConvertAtomics) { + return; + } +} + +bool +AMDGPUPeepholeOpt::runOnFunction(Function &MF) { + mChanged = false; + mF = &MF; + mSTM = &TM.getSubtarget<AMDGPUSubtarget>(); + if (mDebug) { + MF.dump(); + } + mCTX = &MF.getType()->getContext(); + mConvertAtomics = true; + safeNestedForEach(MF.begin(), MF.end(), MF.begin()->begin(), + std::bind1st(std::mem_fun(&AMDGPUPeepholeOpt::instLevelOptimizations), + this)); + + doAtomicConversionIfNeeded(MF); + doIsConstCallConversionIfNeeded(); + + if (mDebug) { + MF.dump(); + } + return mChanged; +} + +bool +AMDGPUPeepholeOpt::optimizeCallInst(BasicBlock::iterator *bbb) { + Instruction *inst = (*bbb); + CallInst *CI = dyn_cast<CallInst>(inst); + if (!CI) { + return false; + } + if (isSigned24BitOps(CI)) { + expandSigned24BitOps(CI); + ++(*bbb); + CI->eraseFromParent(); + return true; + } + if (propagateSamplerInst(CI)) { + return false; + } + if (expandBFI(CI) || expandBFM(CI)) { + ++(*bbb); + CI->eraseFromParent(); + return true; + } + if (convertAccurateDivide(CI)) { + expandAccurateDivide(CI); + ++(*bbb); + CI->eraseFromParent(); + return true; + } + + StringRef calleeName = CI->getOperand(CI->getNumOperands()-1)->getName(); + if (calleeName.startswith("__amdil_is_constant")) { + // If we do not have optimizations, then this + // cannot be properly evaluated, so we add the + // call instruction to a vector and process + // them at the end of processing after the + // samplers have been correctly handled. + if (optLevel == CodeGenOpt::None) { + isConstVec.push_back(CI); + return false; + } else { + Constant *CV = dyn_cast<Constant>(CI->getOperand(0)); + Type *aType = Type::getInt32Ty(*mCTX); + Value *Val = (CV != NULL) ? ConstantInt::get(aType, 1) + : ConstantInt::get(aType, 0); + CI->replaceAllUsesWith(Val); + ++(*bbb); + CI->eraseFromParent(); + return true; + } + } + + if (calleeName.equals("__amdil_is_asic_id_i32")) { + ConstantInt *CV = dyn_cast<ConstantInt>(CI->getOperand(0)); + Type *aType = Type::getInt32Ty(*mCTX); + Value *Val = CV; + if (Val) { + Val = ConstantInt::get(aType, + mSTM->device()->getDeviceFlag() & CV->getZExtValue()); + } else { + Val = ConstantInt::get(aType, 0); + } + CI->replaceAllUsesWith(Val); + ++(*bbb); + CI->eraseFromParent(); + return true; + } + Function *F = dyn_cast<Function>(CI->getOperand(CI->getNumOperands()-1)); + if (!F) { + return false; + } + if (F->getName().startswith("__atom") && !CI->getNumUses() + && F->getName().find("_xchg") == StringRef::npos) { + std::string buffer(F->getName().str() + "_noret"); + F = dyn_cast<Function>( + F->getParent()->getOrInsertFunction(buffer, F->getFunctionType())); + atomicFuncs.push_back(std::make_pair(CI, F)); + } + + if (!mSTM->device()->isSupported(AMDGPUDeviceInfo::ArenaSegment) + && !mSTM->device()->isSupported(AMDGPUDeviceInfo::MultiUAV)) { + return false; + } + if (!mConvertAtomics) { + return false; + } + StringRef name = F->getName(); + if (name.startswith("__atom") && name.find("_g") != StringRef::npos) { + mConvertAtomics = false; + } + return false; +} + +bool +AMDGPUPeepholeOpt::setupBitInsert(Instruction *base, + Instruction *&src, + Constant *&mask, + Constant *&shift) { + if (!base) { + if (mDebug) { + dbgs() << "Null pointer passed into function.\n"; + } + return false; + } + bool andOp = false; + if (base->getOpcode() == Instruction::Shl) { + shift = dyn_cast<Constant>(base->getOperand(1)); + } else if (base->getOpcode() == Instruction::And) { + mask = dyn_cast<Constant>(base->getOperand(1)); + andOp = true; + } else { + if (mDebug) { + dbgs() << "Failed setup with no Shl or And instruction on base opcode!\n"; + } + // If the base is neither a Shl or a And, we don't fit any of the patterns above. + return false; + } + src = dyn_cast<Instruction>(base->getOperand(0)); + if (!src) { + if (mDebug) { + dbgs() << "Failed setup since the base operand is not an instruction!\n"; + } + return false; + } + // If we find an 'and' operation, then we don't need to + // find the next operation as we already know the + // bits that are valid at this point. + if (andOp) { + return true; + } + if (src->getOpcode() == Instruction::Shl && !shift) { + shift = dyn_cast<Constant>(src->getOperand(1)); + src = dyn_cast<Instruction>(src->getOperand(0)); + } else if (src->getOpcode() == Instruction::And && !mask) { + mask = dyn_cast<Constant>(src->getOperand(1)); + } + if (!mask && !shift) { + if (mDebug) { + dbgs() << "Failed setup since both mask and shift are NULL!\n"; + } + // Did not find a constant mask or a shift. + return false; + } + return true; +} +bool +AMDGPUPeepholeOpt::optimizeBitInsert(Instruction *inst) { + if (!inst) { + return false; + } + if (!inst->isBinaryOp()) { + return false; + } + if (inst->getOpcode() != Instruction::Or) { + return false; + } + if (optLevel == CodeGenOpt::None) { + return false; + } + // We want to do an optimization on a sequence of ops that in the end equals a + // single ISA instruction. + // The base pattern for this optimization is - ((A & B) << C) | ((D & E) << F) + // Some simplified versions of this pattern are as follows: + // (A & B) | (D & E) when B & E == 0 && C == 0 && F == 0 + // ((A & B) << C) | (D & E) when B ^ E == 0 && (1 << C) >= E + // (A & B) | ((D & E) << F) when B ^ E == 0 && (1 << F) >= B + // (A & B) | (D << F) when (1 << F) >= B + // (A << C) | (D & E) when (1 << C) >= E + if (mSTM->device()->getGeneration() == AMDGPUDeviceInfo::HD4XXX) { + // The HD4XXX hardware doesn't support the ubit_insert instruction. + return false; + } + Type *aType = inst->getType(); + bool isVector = aType->isVectorTy(); + int numEle = 1; + // This optimization only works on 32bit integers. + if (aType->getScalarType() + != Type::getInt32Ty(inst->getContext())) { + return false; + } + if (isVector) { + const VectorType *VT = dyn_cast<VectorType>(aType); + numEle = VT->getNumElements(); + // We currently cannot support more than 4 elements in a intrinsic and we + // cannot support Vec3 types. + if (numEle > 4 || numEle == 3) { + return false; + } + } + // TODO: Handle vectors. + if (isVector) { + if (mDebug) { + dbgs() << "!!! Vectors are not supported yet!\n"; + } + return false; + } + Instruction *LHSSrc = NULL, *RHSSrc = NULL; + Constant *LHSMask = NULL, *RHSMask = NULL; + Constant *LHSShift = NULL, *RHSShift = NULL; + Instruction *LHS = dyn_cast<Instruction>(inst->getOperand(0)); + Instruction *RHS = dyn_cast<Instruction>(inst->getOperand(1)); + if (!setupBitInsert(LHS, LHSSrc, LHSMask, LHSShift)) { + if (mDebug) { + dbgs() << "Found an OR Operation that failed setup!\n"; + inst->dump(); + if (LHS) { LHS->dump(); } + if (LHSSrc) { LHSSrc->dump(); } + if (LHSMask) { LHSMask->dump(); } + if (LHSShift) { LHSShift->dump(); } + } + // There was an issue with the setup for BitInsert. + return false; + } + if (!setupBitInsert(RHS, RHSSrc, RHSMask, RHSShift)) { + if (mDebug) { + dbgs() << "Found an OR Operation that failed setup!\n"; + inst->dump(); + if (RHS) { RHS->dump(); } + if (RHSSrc) { RHSSrc->dump(); } + if (RHSMask) { RHSMask->dump(); } + if (RHSShift) { RHSShift->dump(); } + } + // There was an issue with the setup for BitInsert. + return false; + } + if (mDebug) { + dbgs() << "Found an OR operation that can possible be optimized to ubit insert!\n"; + dbgs() << "Op: "; inst->dump(); + dbgs() << "LHS: "; if (LHS) { LHS->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "LHS Src: "; if (LHSSrc) { LHSSrc->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "LHS Mask: "; if (LHSMask) { LHSMask->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "LHS Shift: "; if (LHSShift) { LHSShift->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "RHS: "; if (RHS) { RHS->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "RHS Src: "; if (RHSSrc) { RHSSrc->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "RHS Mask: "; if (RHSMask) { RHSMask->dump(); } else { dbgs() << "(None)\n"; } + dbgs() << "RHS Shift: "; if (RHSShift) { RHSShift->dump(); } else { dbgs() << "(None)\n"; } + } + Constant *offset = NULL; + Constant *width = NULL; + uint32_t lhsMaskVal = 0, rhsMaskVal = 0; + uint32_t lhsShiftVal = 0, rhsShiftVal = 0; + uint32_t lhsMaskWidth = 0, rhsMaskWidth = 0; + uint32_t lhsMaskOffset = 0, rhsMaskOffset = 0; + lhsMaskVal = (LHSMask + ? dyn_cast<ConstantInt>(LHSMask)->getZExtValue() : 0); + rhsMaskVal = (RHSMask + ? dyn_cast<ConstantInt>(RHSMask)->getZExtValue() : 0); + lhsShiftVal = (LHSShift + ? dyn_cast<ConstantInt>(LHSShift)->getZExtValue() : 0); + rhsShiftVal = (RHSShift + ? dyn_cast<ConstantInt>(RHSShift)->getZExtValue() : 0); + lhsMaskWidth = lhsMaskVal ? CountPopulation_32(lhsMaskVal) : 32 - lhsShiftVal; + rhsMaskWidth = rhsMaskVal ? CountPopulation_32(rhsMaskVal) : 32 - rhsShiftVal; + lhsMaskOffset = lhsMaskVal ? CountTrailingZeros_32(lhsMaskVal) : lhsShiftVal; + rhsMaskOffset = rhsMaskVal ? CountTrailingZeros_32(rhsMaskVal) : rhsShiftVal; + // TODO: Handle the case of A & B | D & ~B(i.e. inverted masks). + if ((lhsMaskVal || rhsMaskVal) && !(lhsMaskVal ^ rhsMaskVal)) { + return false; + } + if (lhsMaskOffset >= (rhsMaskWidth + rhsMaskOffset)) { + offset = ConstantInt::get(aType, lhsMaskOffset, false); + width = ConstantInt::get(aType, lhsMaskWidth, false); + RHSSrc = RHS; + if (!isMask_32(lhsMaskVal) && !isShiftedMask_32(lhsMaskVal)) { + return false; + } + if (!LHSShift) { + LHSSrc = BinaryOperator::Create(Instruction::LShr, LHSSrc, offset, + "MaskShr", LHS); + } else if (lhsShiftVal != lhsMaskOffset) { + LHSSrc = BinaryOperator::Create(Instruction::LShr, LHSSrc, offset, + "MaskShr", LHS); + } + if (mDebug) { + dbgs() << "Optimizing LHS!\n"; + } + } else if (rhsMaskOffset >= (lhsMaskWidth + lhsMaskOffset)) { + offset = ConstantInt::get(aType, rhsMaskOffset, false); + width = ConstantInt::get(aType, rhsMaskWidth, false); + LHSSrc = RHSSrc; + RHSSrc = LHS; + if (!isMask_32(rhsMaskVal) && !isShiftedMask_32(rhsMaskVal)) { + return false; + } + if (!RHSShift) { + LHSSrc = BinaryOperator::Create(Instruction::LShr, LHSSrc, offset, + "MaskShr", RHS); + } else if (rhsShiftVal != rhsMaskOffset) { + LHSSrc = BinaryOperator::Create(Instruction::LShr, LHSSrc, offset, + "MaskShr", RHS); + } + if (mDebug) { + dbgs() << "Optimizing RHS!\n"; + } + } else { + if (mDebug) { + dbgs() << "Failed constraint 3!\n"; + } + return false; + } + if (mDebug) { + dbgs() << "Width: "; if (width) { width->dump(); } else { dbgs() << "(0)\n"; } + dbgs() << "Offset: "; if (offset) { offset->dump(); } else { dbgs() << "(0)\n"; } + dbgs() << "LHSSrc: "; if (LHSSrc) { LHSSrc->dump(); } else { dbgs() << "(0)\n"; } + dbgs() << "RHSSrc: "; if (RHSSrc) { RHSSrc->dump(); } else { dbgs() << "(0)\n"; } + } + if (!offset || !width) { + if (mDebug) { + dbgs() << "Either width or offset are NULL, failed detection!\n"; + } + return false; + } + // Lets create the function signature. + std::vector<Type *> callTypes; + callTypes.push_back(aType); + callTypes.push_back(aType); + callTypes.push_back(aType); + callTypes.push_back(aType); + FunctionType *funcType = FunctionType::get(aType, callTypes, false); + std::string name = "__amdil_ubit_insert"; + if (isVector) { name += "_v" + itostr(numEle) + "u32"; } else { name += "_u32"; } + Function *Func = + dyn_cast<Function>(inst->getParent()->getParent()->getParent()-> + getOrInsertFunction(StringRef(name), funcType)); + Value *Operands[4] = { + width, + offset, + LHSSrc, + RHSSrc + }; + CallInst *CI = CallInst::Create(Func, Operands, "BitInsertOpt"); + if (mDebug) { + dbgs() << "Old Inst: "; + inst->dump(); + dbgs() << "New Inst: "; + CI->dump(); + dbgs() << "\n\n"; + } + CI->insertBefore(inst); + inst->replaceAllUsesWith(CI); + return true; +} + +bool +AMDGPUPeepholeOpt::optimizeBitExtract(Instruction *inst) { + if (!inst) { + return false; + } + if (!inst->isBinaryOp()) { + return false; + } + if (inst->getOpcode() != Instruction::And) { + return false; + } + if (optLevel == CodeGenOpt::None) { + return false; + } + // We want to do some simple optimizations on Shift right/And patterns. The + // basic optimization is to turn (A >> B) & C where A is a 32bit type, B is a + // value smaller than 32 and C is a mask. If C is a constant value, then the + // following transformation can occur. For signed integers, it turns into the + // function call dst = __amdil_ibit_extract(log2(C), B, A) For unsigned + // integers, it turns into the function call dst = + // __amdil_ubit_extract(log2(C), B, A) The function __amdil_[u|i]bit_extract + // can be found in Section 7.9 of the ATI IL spec of the stream SDK for + // Evergreen hardware. + if (mSTM->device()->getGeneration() == AMDGPUDeviceInfo::HD4XXX) { + // This does not work on HD4XXX hardware. + return false; + } + Type *aType = inst->getType(); + bool isVector = aType->isVectorTy(); + + // XXX Support vector types + if (isVector) { + return false; + } + int numEle = 1; + // This only works on 32bit integers + if (aType->getScalarType() + != Type::getInt32Ty(inst->getContext())) { + return false; + } + if (isVector) { + const VectorType *VT = dyn_cast<VectorType>(aType); + numEle = VT->getNumElements(); + // We currently cannot support more than 4 elements in a intrinsic and we + // cannot support Vec3 types. + if (numEle > 4 || numEle == 3) { + return false; + } + } + BinaryOperator *ShiftInst = dyn_cast<BinaryOperator>(inst->getOperand(0)); + // If the first operand is not a shift instruction, then we can return as it + // doesn't match this pattern. + if (!ShiftInst || !ShiftInst->isShift()) { + return false; + } + // If we are a shift left, then we need don't match this pattern. + if (ShiftInst->getOpcode() == Instruction::Shl) { + return false; + } + bool isSigned = ShiftInst->isArithmeticShift(); + Constant *AndMask = dyn_cast<Constant>(inst->getOperand(1)); + Constant *ShrVal = dyn_cast<Constant>(ShiftInst->getOperand(1)); + // Lets make sure that the shift value and the and mask are constant integers. + if (!AndMask || !ShrVal) { + return false; + } + Constant *newMaskConst; + Constant *shiftValConst; + if (isVector) { + // Handle the vector case + std::vector<Constant *> maskVals; + std::vector<Constant *> shiftVals; + ConstantVector *AndMaskVec = dyn_cast<ConstantVector>(AndMask); + ConstantVector *ShrValVec = dyn_cast<ConstantVector>(ShrVal); + Type *scalarType = AndMaskVec->getType()->getScalarType(); + assert(AndMaskVec->getNumOperands() == + ShrValVec->getNumOperands() && "cannot have a " + "combination where the number of elements to a " + "shift and an and are different!"); + for (size_t x = 0, y = AndMaskVec->getNumOperands(); x < y; ++x) { + ConstantInt *AndCI = dyn_cast<ConstantInt>(AndMaskVec->getOperand(x)); + ConstantInt *ShiftIC = dyn_cast<ConstantInt>(ShrValVec->getOperand(x)); + if (!AndCI || !ShiftIC) { + return false; + } + uint32_t maskVal = (uint32_t)AndCI->getZExtValue(); + if (!isMask_32(maskVal)) { + return false; + } + maskVal = (uint32_t)CountTrailingOnes_32(maskVal); + uint32_t shiftVal = (uint32_t)ShiftIC->getZExtValue(); + // If the mask or shiftval is greater than the bitcount, then break out. + if (maskVal >= 32 || shiftVal >= 32) { + return false; + } + // If the mask val is greater than the the number of original bits left + // then this optimization is invalid. + if (maskVal > (32 - shiftVal)) { + return false; + } + maskVals.push_back(ConstantInt::get(scalarType, maskVal, isSigned)); + shiftVals.push_back(ConstantInt::get(scalarType, shiftVal, isSigned)); + } + newMaskConst = ConstantVector::get(maskVals); + shiftValConst = ConstantVector::get(shiftVals); + } else { + // Handle the scalar case + uint32_t maskVal = (uint32_t)dyn_cast<ConstantInt>(AndMask)->getZExtValue(); + // This must be a mask value where all lower bits are set to 1 and then any + // bit higher is set to 0. + if (!isMask_32(maskVal)) { + return false; + } + maskVal = (uint32_t)CountTrailingOnes_32(maskVal); + // Count the number of bits set in the mask, this is the width of the + // resulting bit set that is extracted from the source value. + uint32_t shiftVal = (uint32_t)dyn_cast<ConstantInt>(ShrVal)->getZExtValue(); + // If the mask or shift val is greater than the bitcount, then break out. + if (maskVal >= 32 || shiftVal >= 32) { + return false; + } + // If the mask val is greater than the the number of original bits left then + // this optimization is invalid. + if (maskVal > (32 - shiftVal)) { + return false; + } + newMaskConst = ConstantInt::get(aType, maskVal, isSigned); + shiftValConst = ConstantInt::get(aType, shiftVal, isSigned); + } + // Lets create the function signature. + std::vector<Type *> callTypes; + callTypes.push_back(aType); + callTypes.push_back(aType); + callTypes.push_back(aType); + FunctionType *funcType = FunctionType::get(aType, callTypes, false); + std::string name = "llvm.AMDGPU.bit.extract.u32"; + if (isVector) { + name += ".v" + itostr(numEle) + "i32"; + } else { + name += "."; + } + // Lets create the function. + Function *Func = + dyn_cast<Function>(inst->getParent()->getParent()->getParent()-> + getOrInsertFunction(StringRef(name), funcType)); + Value *Operands[3] = { + ShiftInst->getOperand(0), + shiftValConst, + newMaskConst + }; + // Lets create the Call with the operands + CallInst *CI = CallInst::Create(Func, Operands, "ByteExtractOpt"); + CI->setDoesNotAccessMemory(); + CI->insertBefore(inst); + inst->replaceAllUsesWith(CI); + return true; +} + +bool +AMDGPUPeepholeOpt::expandBFI(CallInst *CI) { + if (!CI) { + return false; + } + Value *LHS = CI->getOperand(CI->getNumOperands() - 1); + if (!LHS->getName().startswith("__amdil_bfi")) { + return false; + } + Type* type = CI->getOperand(0)->getType(); + Constant *negOneConst = NULL; + if (type->isVectorTy()) { + std::vector<Constant *> negOneVals; + negOneConst = ConstantInt::get(CI->getContext(), + APInt(32, StringRef("-1"), 10)); + for (size_t x = 0, + y = dyn_cast<VectorType>(type)->getNumElements(); x < y; ++x) { + negOneVals.push_back(negOneConst); + } + negOneConst = ConstantVector::get(negOneVals); + } else { + negOneConst = ConstantInt::get(CI->getContext(), + APInt(32, StringRef("-1"), 10)); + } + // __amdil_bfi => (A & B) | (~A & C) + BinaryOperator *lhs = + BinaryOperator::Create(Instruction::And, CI->getOperand(0), + CI->getOperand(1), "bfi_and", CI); + BinaryOperator *rhs = + BinaryOperator::Create(Instruction::Xor, CI->getOperand(0), negOneConst, + "bfi_not", CI); + rhs = BinaryOperator::Create(Instruction::And, rhs, CI->getOperand(2), + "bfi_and", CI); + lhs = BinaryOperator::Create(Instruction::Or, lhs, rhs, "bfi_or", CI); + CI->replaceAllUsesWith(lhs); + return true; +} + +bool +AMDGPUPeepholeOpt::expandBFM(CallInst *CI) { + if (!CI) { + return false; + } + Value *LHS = CI->getOperand(CI->getNumOperands() - 1); + if (!LHS->getName().startswith("__amdil_bfm")) { + return false; + } + // __amdil_bfm => ((1 << (src0 & 0x1F)) - 1) << (src1 & 0x1f) + Constant *newMaskConst = NULL; + Constant *newShiftConst = NULL; + Type* type = CI->getOperand(0)->getType(); + if (type->isVectorTy()) { + std::vector<Constant*> newMaskVals, newShiftVals; + newMaskConst = ConstantInt::get(Type::getInt32Ty(*mCTX), 0x1F); + newShiftConst = ConstantInt::get(Type::getInt32Ty(*mCTX), 1); + for (size_t x = 0, + y = dyn_cast<VectorType>(type)->getNumElements(); x < y; ++x) { + newMaskVals.push_back(newMaskConst); + newShiftVals.push_back(newShiftConst); + } + newMaskConst = ConstantVector::get(newMaskVals); + newShiftConst = ConstantVector::get(newShiftVals); + } else { + newMaskConst = ConstantInt::get(Type::getInt32Ty(*mCTX), 0x1F); + newShiftConst = ConstantInt::get(Type::getInt32Ty(*mCTX), 1); + } + BinaryOperator *lhs = + BinaryOperator::Create(Instruction::And, CI->getOperand(0), + newMaskConst, "bfm_mask", CI); + lhs = BinaryOperator::Create(Instruction::Shl, newShiftConst, + lhs, "bfm_shl", CI); + lhs = BinaryOperator::Create(Instruction::Sub, lhs, + newShiftConst, "bfm_sub", CI); + BinaryOperator *rhs = + BinaryOperator::Create(Instruction::And, CI->getOperand(1), + newMaskConst, "bfm_mask", CI); + lhs = BinaryOperator::Create(Instruction::Shl, lhs, rhs, "bfm_shl", CI); + CI->replaceAllUsesWith(lhs); + return true; +} + +bool +AMDGPUPeepholeOpt::instLevelOptimizations(BasicBlock::iterator *bbb) { + Instruction *inst = (*bbb); + if (optimizeCallInst(bbb)) { + return true; + } + if (optimizeBitExtract(inst)) { + return false; + } + if (optimizeBitInsert(inst)) { + return false; + } + if (correctMisalignedMemOp(inst)) { + return false; + } + return false; +} +bool +AMDGPUPeepholeOpt::correctMisalignedMemOp(Instruction *inst) { + LoadInst *linst = dyn_cast<LoadInst>(inst); + StoreInst *sinst = dyn_cast<StoreInst>(inst); + unsigned alignment; + Type* Ty = inst->getType(); + if (linst) { + alignment = linst->getAlignment(); + Ty = inst->getType(); + } else if (sinst) { + alignment = sinst->getAlignment(); + Ty = sinst->getValueOperand()->getType(); + } else { + return false; + } + unsigned size = getTypeSize(Ty); + if (size == alignment || size < alignment) { + return false; + } + if (!Ty->isStructTy()) { + return false; + } + if (alignment < 4) { + if (linst) { + linst->setAlignment(0); + return true; + } else if (sinst) { + sinst->setAlignment(0); + return true; + } + } + return false; +} +bool +AMDGPUPeepholeOpt::isSigned24BitOps(CallInst *CI) { + if (!CI) { + return false; + } + Value *LHS = CI->getOperand(CI->getNumOperands() - 1); + std::string namePrefix = LHS->getName().substr(0, 14); + if (namePrefix != "__amdil_imad24" && namePrefix != "__amdil_imul24" + && namePrefix != "__amdil__imul24_high") { + return false; + } + if (mSTM->device()->usesHardware(AMDGPUDeviceInfo::Signed24BitOps)) { + return false; + } + return true; +} + +void +AMDGPUPeepholeOpt::expandSigned24BitOps(CallInst *CI) { + assert(isSigned24BitOps(CI) && "Must be a " + "signed 24 bit operation to call this function!"); + Value *LHS = CI->getOperand(CI->getNumOperands()-1); + // On 7XX and 8XX we do not have signed 24bit, so we need to + // expand it to the following: + // imul24 turns into 32bit imul + // imad24 turns into 32bit imad + // imul24_high turns into 32bit imulhigh + if (LHS->getName().substr(0, 14) == "__amdil_imad24") { + Type *aType = CI->getOperand(0)->getType(); + bool isVector = aType->isVectorTy(); + int numEle = isVector ? dyn_cast<VectorType>(aType)->getNumElements() : 1; + std::vector<Type*> callTypes; + callTypes.push_back(CI->getOperand(0)->getType()); + callTypes.push_back(CI->getOperand(1)->getType()); + callTypes.push_back(CI->getOperand(2)->getType()); + FunctionType *funcType = + FunctionType::get(CI->getOperand(0)->getType(), callTypes, false); + std::string name = "__amdil_imad"; + if (isVector) { + name += "_v" + itostr(numEle) + "i32"; + } else { + name += "_i32"; + } + Function *Func = dyn_cast<Function>( + CI->getParent()->getParent()->getParent()-> + getOrInsertFunction(StringRef(name), funcType)); + Value *Operands[3] = { + CI->getOperand(0), + CI->getOperand(1), + CI->getOperand(2) + }; + CallInst *nCI = CallInst::Create(Func, Operands, "imad24"); + nCI->insertBefore(CI); + CI->replaceAllUsesWith(nCI); + } else if (LHS->getName().substr(0, 14) == "__amdil_imul24") { + BinaryOperator *mulOp = + BinaryOperator::Create(Instruction::Mul, CI->getOperand(0), + CI->getOperand(1), "imul24", CI); + CI->replaceAllUsesWith(mulOp); + } else if (LHS->getName().substr(0, 19) == "__amdil_imul24_high") { + Type *aType = CI->getOperand(0)->getType(); + + bool isVector = aType->isVectorTy(); + int numEle = isVector ? dyn_cast<VectorType>(aType)->getNumElements() : 1; + std::vector<Type*> callTypes; + callTypes.push_back(CI->getOperand(0)->getType()); + callTypes.push_back(CI->getOperand(1)->getType()); + FunctionType *funcType = + FunctionType::get(CI->getOperand(0)->getType(), callTypes, false); + std::string name = "__amdil_imul_high"; + if (isVector) { + name += "_v" + itostr(numEle) + "i32"; + } else { + name += "_i32"; + } + Function *Func = dyn_cast<Function>( + CI->getParent()->getParent()->getParent()-> + getOrInsertFunction(StringRef(name), funcType)); + Value *Operands[2] = { + CI->getOperand(0), + CI->getOperand(1) + }; + CallInst *nCI = CallInst::Create(Func, Operands, "imul24_high"); + nCI->insertBefore(CI); + CI->replaceAllUsesWith(nCI); + } +} + +bool +AMDGPUPeepholeOpt::isRWGLocalOpt(CallInst *CI) { + return (CI != NULL + && CI->getOperand(CI->getNumOperands() - 1)->getName() + == "__amdil_get_local_size_int"); +} + +bool +AMDGPUPeepholeOpt::convertAccurateDivide(CallInst *CI) { + if (!CI) { + return false; + } + if (mSTM->device()->getGeneration() == AMDGPUDeviceInfo::HD6XXX + && (mSTM->getDeviceName() == "cayman")) { + return false; + } + return CI->getOperand(CI->getNumOperands() - 1)->getName().substr(0, 20) + == "__amdil_improved_div"; +} + +void +AMDGPUPeepholeOpt::expandAccurateDivide(CallInst *CI) { + assert(convertAccurateDivide(CI) + && "expanding accurate divide can only happen if it is expandable!"); + BinaryOperator *divOp = + BinaryOperator::Create(Instruction::FDiv, CI->getOperand(0), + CI->getOperand(1), "fdiv32", CI); + CI->replaceAllUsesWith(divOp); +} + +bool +AMDGPUPeepholeOpt::propagateSamplerInst(CallInst *CI) { + if (optLevel != CodeGenOpt::None) { + return false; + } + + if (!CI) { + return false; + } + + unsigned funcNameIdx = 0; + funcNameIdx = CI->getNumOperands() - 1; + StringRef calleeName = CI->getOperand(funcNameIdx)->getName(); + if (calleeName != "__amdil_image2d_read_norm" + && calleeName != "__amdil_image2d_read_unnorm" + && calleeName != "__amdil_image3d_read_norm" + && calleeName != "__amdil_image3d_read_unnorm") { + return false; + } + + unsigned samplerIdx = 2; + samplerIdx = 1; + Value *sampler = CI->getOperand(samplerIdx); + LoadInst *lInst = dyn_cast<LoadInst>(sampler); + if (!lInst) { + return false; + } + + if (lInst->getPointerAddressSpace() != AMDGPUAS::PRIVATE_ADDRESS) { + return false; + } + + GlobalVariable *gv = dyn_cast<GlobalVariable>(lInst->getPointerOperand()); + // If we are loading from what is not a global value, then we + // fail and return. + if (!gv) { + return false; + } + + // If we don't have an initializer or we have an initializer and + // the initializer is not a 32bit integer, we fail. + if (!gv->hasInitializer() + || !gv->getInitializer()->getType()->isIntegerTy(32)) { + return false; + } + + // Now that we have the global variable initializer, lets replace + // all uses of the load instruction with the samplerVal and + // reparse the __amdil_is_constant() function. + Constant *samplerVal = gv->getInitializer(); + lInst->replaceAllUsesWith(samplerVal); + return true; +} + +bool +AMDGPUPeepholeOpt::doInitialization(Module &M) { + return false; +} + +bool +AMDGPUPeepholeOpt::doFinalization(Module &M) { + return false; +} + +void +AMDGPUPeepholeOpt::getAnalysisUsage(AnalysisUsage &AU) const { + AU.addRequired<MachineFunctionAnalysis>(); + FunctionPass::getAnalysisUsage(AU); + AU.setPreservesAll(); +} + +size_t AMDGPUPeepholeOpt::getTypeSize(Type * const T, bool dereferencePtr) { + size_t size = 0; + if (!T) { + return size; + } + switch (T->getTypeID()) { + case Type::X86_FP80TyID: + case Type::FP128TyID: + case Type::PPC_FP128TyID: + case Type::LabelTyID: + assert(0 && "These types are not supported by this backend"); + default: + case Type::FloatTyID: + case Type::DoubleTyID: + size = T->getPrimitiveSizeInBits() >> 3; + break; + case Type::PointerTyID: + size = getTypeSize(dyn_cast<PointerType>(T), dereferencePtr); + break; + case Type::IntegerTyID: + size = getTypeSize(dyn_cast<IntegerType>(T), dereferencePtr); + break; + case Type::StructTyID: + size = getTypeSize(dyn_cast<StructType>(T), dereferencePtr); + break; + case Type::ArrayTyID: + size = getTypeSize(dyn_cast<ArrayType>(T), dereferencePtr); + break; + case Type::FunctionTyID: + size = getTypeSize(dyn_cast<FunctionType>(T), dereferencePtr); + break; + case Type::VectorTyID: + size = getTypeSize(dyn_cast<VectorType>(T), dereferencePtr); + break; + }; + return size; +} + +size_t AMDGPUPeepholeOpt::getTypeSize(StructType * const ST, + bool dereferencePtr) { + size_t size = 0; + if (!ST) { + return size; + } + Type *curType; + StructType::element_iterator eib; + StructType::element_iterator eie; + for (eib = ST->element_begin(), eie = ST->element_end(); eib != eie; ++eib) { + curType = *eib; + size += getTypeSize(curType, dereferencePtr); + } + return size; +} + +size_t AMDGPUPeepholeOpt::getTypeSize(IntegerType * const IT, + bool dereferencePtr) { + return IT ? (IT->getBitWidth() >> 3) : 0; +} + +size_t AMDGPUPeepholeOpt::getTypeSize(FunctionType * const FT, + bool dereferencePtr) { + assert(0 && "Should not be able to calculate the size of an function type"); + return 0; +} + +size_t AMDGPUPeepholeOpt::getTypeSize(ArrayType * const AT, + bool dereferencePtr) { + return (size_t)(AT ? (getTypeSize(AT->getElementType(), + dereferencePtr) * AT->getNumElements()) + : 0); +} + +size_t AMDGPUPeepholeOpt::getTypeSize(VectorType * const VT, + bool dereferencePtr) { + return VT ? (VT->getBitWidth() >> 3) : 0; +} + +size_t AMDGPUPeepholeOpt::getTypeSize(PointerType * const PT, + bool dereferencePtr) { + if (!PT) { + return 0; + } + Type *CT = PT->getElementType(); + if (CT->getTypeID() == Type::StructTyID && + PT->getAddressSpace() == AMDGPUAS::PRIVATE_ADDRESS) { + return getTypeSize(dyn_cast<StructType>(CT)); + } else if (dereferencePtr) { + size_t size = 0; + for (size_t x = 0, y = PT->getNumContainedTypes(); x < y; ++x) { + size += getTypeSize(PT->getContainedType(x), dereferencePtr); + } + return size; + } else { + return 4; + } +} + +size_t AMDGPUPeepholeOpt::getTypeSize(OpaqueType * const OT, + bool dereferencePtr) { + //assert(0 && "Should not be able to calculate the size of an opaque type"); + return 4; +} |