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Diffstat (limited to 'lib/Transforms/Vectorize/BBVectorize.cpp')
| -rw-r--r-- | lib/Transforms/Vectorize/BBVectorize.cpp | 3282 |
1 files changed, 0 insertions, 3282 deletions
diff --git a/lib/Transforms/Vectorize/BBVectorize.cpp b/lib/Transforms/Vectorize/BBVectorize.cpp deleted file mode 100644 index 78453aaa16ceb..0000000000000 --- a/lib/Transforms/Vectorize/BBVectorize.cpp +++ /dev/null @@ -1,3282 +0,0 @@ -//===- BBVectorize.cpp - A Basic-Block Vectorizer -------------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements a basic-block vectorization pass. The algorithm was -// inspired by that used by the Vienna MAP Vectorizor by Franchetti and Kral, -// et al. It works by looking for chains of pairable operations and then -// pairing them. -// -//===----------------------------------------------------------------------===// - -#define BBV_NAME "bb-vectorize" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/DenseSet.h" -#include "llvm/ADT/STLExtras.h" -#include "llvm/ADT/SmallSet.h" -#include "llvm/ADT/SmallVector.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/ADT/StringExtras.h" -#include "llvm/Analysis/AliasAnalysis.h" -#include "llvm/Analysis/AliasSetTracker.h" -#include "llvm/Analysis/GlobalsModRef.h" -#include "llvm/Analysis/ScalarEvolution.h" -#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h" -#include "llvm/Analysis/ScalarEvolutionExpressions.h" -#include "llvm/Analysis/TargetLibraryInfo.h" -#include "llvm/Analysis/TargetTransformInfo.h" -#include "llvm/Analysis/ValueTracking.h" -#include "llvm/IR/Constants.h" -#include "llvm/IR/DataLayout.h" -#include "llvm/IR/DerivedTypes.h" -#include "llvm/IR/Dominators.h" -#include "llvm/IR/Function.h" -#include "llvm/IR/Instructions.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/Intrinsics.h" -#include "llvm/IR/LLVMContext.h" -#include "llvm/IR/Metadata.h" -#include "llvm/IR/Module.h" -#include "llvm/IR/Type.h" -#include "llvm/IR/ValueHandle.h" -#include "llvm/Pass.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/raw_ostream.h" -#include "llvm/Transforms/Utils/Local.h" -#include "llvm/Transforms/Vectorize.h" -#include <algorithm> -using namespace llvm; - -#define DEBUG_TYPE BBV_NAME - -static cl::opt<bool> -IgnoreTargetInfo("bb-vectorize-ignore-target-info", cl::init(false), - cl::Hidden, cl::desc("Ignore target information")); - -static cl::opt<unsigned> -ReqChainDepth("bb-vectorize-req-chain-depth", cl::init(6), cl::Hidden, - cl::desc("The required chain depth for vectorization")); - -static cl::opt<bool> -UseChainDepthWithTI("bb-vectorize-use-chain-depth", cl::init(false), - cl::Hidden, cl::desc("Use the chain depth requirement with" - " target information")); - -static cl::opt<unsigned> -SearchLimit("bb-vectorize-search-limit", cl::init(400), cl::Hidden, - cl::desc("The maximum search distance for instruction pairs")); - -static cl::opt<bool> -SplatBreaksChain("bb-vectorize-splat-breaks-chain", cl::init(false), cl::Hidden, - cl::desc("Replicating one element to a pair breaks the chain")); - -static cl::opt<unsigned> -VectorBits("bb-vectorize-vector-bits", cl::init(128), cl::Hidden, - cl::desc("The size of the native vector registers")); - -static cl::opt<unsigned> -MaxIter("bb-vectorize-max-iter", cl::init(0), cl::Hidden, - cl::desc("The maximum number of pairing iterations")); - -static cl::opt<bool> -Pow2LenOnly("bb-vectorize-pow2-len-only", cl::init(false), cl::Hidden, - cl::desc("Don't try to form non-2^n-length vectors")); - -static cl::opt<unsigned> -MaxInsts("bb-vectorize-max-instr-per-group", cl::init(500), cl::Hidden, - cl::desc("The maximum number of pairable instructions per group")); - -static cl::opt<unsigned> -MaxPairs("bb-vectorize-max-pairs-per-group", cl::init(3000), cl::Hidden, - cl::desc("The maximum number of candidate instruction pairs per group")); - -static cl::opt<unsigned> -MaxCandPairsForCycleCheck("bb-vectorize-max-cycle-check-pairs", cl::init(200), - cl::Hidden, cl::desc("The maximum number of candidate pairs with which to use" - " a full cycle check")); - -static cl::opt<bool> -NoBools("bb-vectorize-no-bools", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize boolean (i1) values")); - -static cl::opt<bool> -NoInts("bb-vectorize-no-ints", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize integer values")); - -static cl::opt<bool> -NoFloats("bb-vectorize-no-floats", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize floating-point values")); - -// FIXME: This should default to false once pointer vector support works. -static cl::opt<bool> -NoPointers("bb-vectorize-no-pointers", cl::init(/*false*/ true), cl::Hidden, - cl::desc("Don't try to vectorize pointer values")); - -static cl::opt<bool> -NoCasts("bb-vectorize-no-casts", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize casting (conversion) operations")); - -static cl::opt<bool> -NoMath("bb-vectorize-no-math", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize floating-point math intrinsics")); - -static cl::opt<bool> - NoBitManipulation("bb-vectorize-no-bitmanip", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize BitManipulation intrinsics")); - -static cl::opt<bool> -NoFMA("bb-vectorize-no-fma", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize the fused-multiply-add intrinsic")); - -static cl::opt<bool> -NoSelect("bb-vectorize-no-select", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize select instructions")); - -static cl::opt<bool> -NoCmp("bb-vectorize-no-cmp", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize comparison instructions")); - -static cl::opt<bool> -NoGEP("bb-vectorize-no-gep", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize getelementptr instructions")); - -static cl::opt<bool> -NoMemOps("bb-vectorize-no-mem-ops", cl::init(false), cl::Hidden, - cl::desc("Don't try to vectorize loads and stores")); - -static cl::opt<bool> -AlignedOnly("bb-vectorize-aligned-only", cl::init(false), cl::Hidden, - cl::desc("Only generate aligned loads and stores")); - -static cl::opt<bool> -NoMemOpBoost("bb-vectorize-no-mem-op-boost", - cl::init(false), cl::Hidden, - cl::desc("Don't boost the chain-depth contribution of loads and stores")); - -static cl::opt<bool> -FastDep("bb-vectorize-fast-dep", cl::init(false), cl::Hidden, - cl::desc("Use a fast instruction dependency analysis")); - -#ifndef NDEBUG -static cl::opt<bool> -DebugInstructionExamination("bb-vectorize-debug-instruction-examination", - cl::init(false), cl::Hidden, - cl::desc("When debugging is enabled, output information on the" - " instruction-examination process")); -static cl::opt<bool> -DebugCandidateSelection("bb-vectorize-debug-candidate-selection", - cl::init(false), cl::Hidden, - cl::desc("When debugging is enabled, output information on the" - " candidate-selection process")); -static cl::opt<bool> -DebugPairSelection("bb-vectorize-debug-pair-selection", - cl::init(false), cl::Hidden, - cl::desc("When debugging is enabled, output information on the" - " pair-selection process")); -static cl::opt<bool> -DebugCycleCheck("bb-vectorize-debug-cycle-check", - cl::init(false), cl::Hidden, - cl::desc("When debugging is enabled, output information on the" - " cycle-checking process")); - -static cl::opt<bool> -PrintAfterEveryPair("bb-vectorize-debug-print-after-every-pair", - cl::init(false), cl::Hidden, - cl::desc("When debugging is enabled, dump the basic block after" - " every pair is fused")); -#endif - -STATISTIC(NumFusedOps, "Number of operations fused by bb-vectorize"); - -namespace { - struct BBVectorize : public BasicBlockPass { - static char ID; // Pass identification, replacement for typeid - - const VectorizeConfig Config; - - BBVectorize(const VectorizeConfig &C = VectorizeConfig()) - : BasicBlockPass(ID), Config(C) { - initializeBBVectorizePass(*PassRegistry::getPassRegistry()); - } - - BBVectorize(Pass *P, Function &F, const VectorizeConfig &C) - : BasicBlockPass(ID), Config(C) { - AA = &P->getAnalysis<AAResultsWrapperPass>().getAAResults(); - DT = &P->getAnalysis<DominatorTreeWrapperPass>().getDomTree(); - SE = &P->getAnalysis<ScalarEvolutionWrapperPass>().getSE(); - TLI = &P->getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(); - TTI = IgnoreTargetInfo - ? nullptr - : &P->getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F); - } - - typedef std::pair<Value *, Value *> ValuePair; - typedef std::pair<ValuePair, int> ValuePairWithCost; - typedef std::pair<ValuePair, size_t> ValuePairWithDepth; - typedef std::pair<ValuePair, ValuePair> VPPair; // A ValuePair pair - typedef std::pair<VPPair, unsigned> VPPairWithType; - - AliasAnalysis *AA; - DominatorTree *DT; - ScalarEvolution *SE; - const TargetLibraryInfo *TLI; - const TargetTransformInfo *TTI; - - // FIXME: const correct? - - bool vectorizePairs(BasicBlock &BB, bool NonPow2Len = false); - - bool getCandidatePairs(BasicBlock &BB, - BasicBlock::iterator &Start, - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<ValuePair, int> &CandidatePairCostSavings, - std::vector<Value *> &PairableInsts, bool NonPow2Len); - - // FIXME: The current implementation does not account for pairs that - // are connected in multiple ways. For example: - // C1 = A1 / A2; C2 = A2 / A1 (which may be both direct and a swap) - enum PairConnectionType { - PairConnectionDirect, - PairConnectionSwap, - PairConnectionSplat - }; - - void computeConnectedPairs( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes); - - void buildDepMap(BasicBlock &BB, - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - std::vector<Value *> &PairableInsts, - DenseSet<ValuePair> &PairableInstUsers); - - void choosePairs(DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - DenseMap<ValuePair, int> &CandidatePairCostSavings, - std::vector<Value *> &PairableInsts, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<Value *, Value *>& ChosenPairs); - - void fuseChosenPairs(BasicBlock &BB, - std::vector<Value *> &PairableInsts, - DenseMap<Value *, Value *>& ChosenPairs, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps); - - - bool isInstVectorizable(Instruction *I, bool &IsSimpleLoadStore); - - bool areInstsCompatible(Instruction *I, Instruction *J, - bool IsSimpleLoadStore, bool NonPow2Len, - int &CostSavings, int &FixedOrder); - - bool trackUsesOfI(DenseSet<Value *> &Users, - AliasSetTracker &WriteSet, Instruction *I, - Instruction *J, bool UpdateUsers = true, - DenseSet<ValuePair> *LoadMoveSetPairs = nullptr); - - void computePairsConnectedTo( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - ValuePair P); - - bool pairsConflict(ValuePair P, ValuePair Q, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<ValuePair, std::vector<ValuePair> > - *PairableInstUserMap = nullptr, - DenseSet<VPPair> *PairableInstUserPairSet = nullptr); - - bool pairWillFormCycle(ValuePair P, - DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUsers, - DenseSet<ValuePair> &CurrentPairs); - - void pruneDAGFor( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap, - DenseSet<VPPair> &PairableInstUserPairSet, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<ValuePair, size_t> &DAG, - DenseSet<ValuePair> &PrunedDAG, ValuePair J, - bool UseCycleCheck); - - void buildInitialDAGFor( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<ValuePair, size_t> &DAG, ValuePair J); - - void findBestDAGFor( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - DenseMap<ValuePair, int> &CandidatePairCostSavings, - std::vector<Value *> &PairableInsts, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap, - DenseSet<VPPair> &PairableInstUserPairSet, - DenseMap<Value *, Value *> &ChosenPairs, - DenseSet<ValuePair> &BestDAG, size_t &BestMaxDepth, - int &BestEffSize, Value *II, std::vector<Value *>&JJ, - bool UseCycleCheck); - - Value *getReplacementPointerInput(LLVMContext& Context, Instruction *I, - Instruction *J, unsigned o); - - void fillNewShuffleMask(LLVMContext& Context, Instruction *J, - unsigned MaskOffset, unsigned NumInElem, - unsigned NumInElem1, unsigned IdxOffset, - std::vector<Constant*> &Mask); - - Value *getReplacementShuffleMask(LLVMContext& Context, Instruction *I, - Instruction *J); - - bool expandIEChain(LLVMContext& Context, Instruction *I, Instruction *J, - unsigned o, Value *&LOp, unsigned numElemL, - Type *ArgTypeL, Type *ArgTypeR, bool IBeforeJ, - unsigned IdxOff = 0); - - Value *getReplacementInput(LLVMContext& Context, Instruction *I, - Instruction *J, unsigned o, bool IBeforeJ); - - void getReplacementInputsForPair(LLVMContext& Context, Instruction *I, - Instruction *J, SmallVectorImpl<Value *> &ReplacedOperands, - bool IBeforeJ); - - void replaceOutputsOfPair(LLVMContext& Context, Instruction *I, - Instruction *J, Instruction *K, - Instruction *&InsertionPt, Instruction *&K1, - Instruction *&K2); - - void collectPairLoadMoveSet(BasicBlock &BB, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<Value *, std::vector<Value *> > &LoadMoveSet, - DenseSet<ValuePair> &LoadMoveSetPairs, - Instruction *I); - - void collectLoadMoveSet(BasicBlock &BB, - std::vector<Value *> &PairableInsts, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<Value *, std::vector<Value *> > &LoadMoveSet, - DenseSet<ValuePair> &LoadMoveSetPairs); - - bool canMoveUsesOfIAfterJ(BasicBlock &BB, - DenseSet<ValuePair> &LoadMoveSetPairs, - Instruction *I, Instruction *J); - - void moveUsesOfIAfterJ(BasicBlock &BB, - DenseSet<ValuePair> &LoadMoveSetPairs, - Instruction *&InsertionPt, - Instruction *I, Instruction *J); - - bool vectorizeBB(BasicBlock &BB) { - if (skipBasicBlock(BB)) - return false; - if (!DT->isReachableFromEntry(&BB)) { - DEBUG(dbgs() << "BBV: skipping unreachable " << BB.getName() << - " in " << BB.getParent()->getName() << "\n"); - return false; - } - - DEBUG(if (TTI) dbgs() << "BBV: using target information\n"); - - bool changed = false; - // Iterate a sufficient number of times to merge types of size 1 bit, - // then 2 bits, then 4, etc. up to half of the target vector width of the - // target vector register. - unsigned n = 1; - for (unsigned v = 2; - (TTI || v <= Config.VectorBits) && - (!Config.MaxIter || n <= Config.MaxIter); - v *= 2, ++n) { - DEBUG(dbgs() << "BBV: fusing loop #" << n << - " for " << BB.getName() << " in " << - BB.getParent()->getName() << "...\n"); - if (vectorizePairs(BB)) - changed = true; - else - break; - } - - if (changed && !Pow2LenOnly) { - ++n; - for (; !Config.MaxIter || n <= Config.MaxIter; ++n) { - DEBUG(dbgs() << "BBV: fusing for non-2^n-length vectors loop #: " << - n << " for " << BB.getName() << " in " << - BB.getParent()->getName() << "...\n"); - if (!vectorizePairs(BB, true)) break; - } - } - - DEBUG(dbgs() << "BBV: done!\n"); - return changed; - } - - bool runOnBasicBlock(BasicBlock &BB) override { - // OptimizeNone check deferred to vectorizeBB(). - - AA = &getAnalysis<AAResultsWrapperPass>().getAAResults(); - DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree(); - SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE(); - TLI = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(); - TTI = IgnoreTargetInfo - ? nullptr - : &getAnalysis<TargetTransformInfoWrapperPass>().getTTI( - *BB.getParent()); - - return vectorizeBB(BB); - } - - void getAnalysisUsage(AnalysisUsage &AU) const override { - BasicBlockPass::getAnalysisUsage(AU); - AU.addRequired<AAResultsWrapperPass>(); - AU.addRequired<DominatorTreeWrapperPass>(); - AU.addRequired<ScalarEvolutionWrapperPass>(); - AU.addRequired<TargetLibraryInfoWrapperPass>(); - AU.addRequired<TargetTransformInfoWrapperPass>(); - AU.addPreserved<DominatorTreeWrapperPass>(); - AU.addPreserved<GlobalsAAWrapperPass>(); - AU.addPreserved<ScalarEvolutionWrapperPass>(); - AU.addPreserved<SCEVAAWrapperPass>(); - AU.setPreservesCFG(); - } - - static inline VectorType *getVecTypeForPair(Type *ElemTy, Type *Elem2Ty) { - assert(ElemTy->getScalarType() == Elem2Ty->getScalarType() && - "Cannot form vector from incompatible scalar types"); - Type *STy = ElemTy->getScalarType(); - - unsigned numElem; - if (VectorType *VTy = dyn_cast<VectorType>(ElemTy)) { - numElem = VTy->getNumElements(); - } else { - numElem = 1; - } - - if (VectorType *VTy = dyn_cast<VectorType>(Elem2Ty)) { - numElem += VTy->getNumElements(); - } else { - numElem += 1; - } - - return VectorType::get(STy, numElem); - } - - static inline void getInstructionTypes(Instruction *I, - Type *&T1, Type *&T2) { - if (StoreInst *SI = dyn_cast<StoreInst>(I)) { - // For stores, it is the value type, not the pointer type that matters - // because the value is what will come from a vector register. - - Value *IVal = SI->getValueOperand(); - T1 = IVal->getType(); - } else { - T1 = I->getType(); - } - - if (CastInst *CI = dyn_cast<CastInst>(I)) - T2 = CI->getSrcTy(); - else - T2 = T1; - - if (SelectInst *SI = dyn_cast<SelectInst>(I)) { - T2 = SI->getCondition()->getType(); - } else if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(I)) { - T2 = SI->getOperand(0)->getType(); - } else if (CmpInst *CI = dyn_cast<CmpInst>(I)) { - T2 = CI->getOperand(0)->getType(); - } - } - - // Returns the weight associated with the provided value. A chain of - // candidate pairs has a length given by the sum of the weights of its - // members (one weight per pair; the weight of each member of the pair - // is assumed to be the same). This length is then compared to the - // chain-length threshold to determine if a given chain is significant - // enough to be vectorized. The length is also used in comparing - // candidate chains where longer chains are considered to be better. - // Note: when this function returns 0, the resulting instructions are - // not actually fused. - inline size_t getDepthFactor(Value *V) { - // InsertElement and ExtractElement have a depth factor of zero. This is - // for two reasons: First, they cannot be usefully fused. Second, because - // the pass generates a lot of these, they can confuse the simple metric - // used to compare the dags in the next iteration. Thus, giving them a - // weight of zero allows the pass to essentially ignore them in - // subsequent iterations when looking for vectorization opportunities - // while still tracking dependency chains that flow through those - // instructions. - if (isa<InsertElementInst>(V) || isa<ExtractElementInst>(V)) - return 0; - - // Give a load or store half of the required depth so that load/store - // pairs will vectorize. - if (!Config.NoMemOpBoost && (isa<LoadInst>(V) || isa<StoreInst>(V))) - return Config.ReqChainDepth/2; - - return 1; - } - - // Returns the cost of the provided instruction using TTI. - // This does not handle loads and stores. - unsigned getInstrCost(unsigned Opcode, Type *T1, Type *T2, - TargetTransformInfo::OperandValueKind Op1VK = - TargetTransformInfo::OK_AnyValue, - TargetTransformInfo::OperandValueKind Op2VK = - TargetTransformInfo::OK_AnyValue, - const Instruction *I = nullptr) { - switch (Opcode) { - default: break; - case Instruction::GetElementPtr: - // We mark this instruction as zero-cost because scalar GEPs are usually - // lowered to the instruction addressing mode. At the moment we don't - // generate vector GEPs. - return 0; - case Instruction::Br: - return TTI->getCFInstrCost(Opcode); - case Instruction::PHI: - return 0; - case Instruction::Add: - case Instruction::FAdd: - case Instruction::Sub: - case Instruction::FSub: - case Instruction::Mul: - case Instruction::FMul: - case Instruction::UDiv: - case Instruction::SDiv: - case Instruction::FDiv: - case Instruction::URem: - case Instruction::SRem: - case Instruction::FRem: - case Instruction::Shl: - case Instruction::LShr: - case Instruction::AShr: - case Instruction::And: - case Instruction::Or: - case Instruction::Xor: - return TTI->getArithmeticInstrCost(Opcode, T1, Op1VK, Op2VK); - case Instruction::Select: - case Instruction::ICmp: - case Instruction::FCmp: - return TTI->getCmpSelInstrCost(Opcode, T1, T2, I); - case Instruction::ZExt: - case Instruction::SExt: - case Instruction::FPToUI: - case Instruction::FPToSI: - case Instruction::FPExt: - case Instruction::PtrToInt: - case Instruction::IntToPtr: - case Instruction::SIToFP: - case Instruction::UIToFP: - case Instruction::Trunc: - case Instruction::FPTrunc: - case Instruction::BitCast: - case Instruction::ShuffleVector: - return TTI->getCastInstrCost(Opcode, T1, T2, I); - } - - return 1; - } - - // This determines the relative offset of two loads or stores, returning - // true if the offset could be determined to be some constant value. - // For example, if OffsetInElmts == 1, then J accesses the memory directly - // after I; if OffsetInElmts == -1 then I accesses the memory - // directly after J. - bool getPairPtrInfo(Instruction *I, Instruction *J, - Value *&IPtr, Value *&JPtr, unsigned &IAlignment, unsigned &JAlignment, - unsigned &IAddressSpace, unsigned &JAddressSpace, - int64_t &OffsetInElmts, bool ComputeOffset = true) { - OffsetInElmts = 0; - if (LoadInst *LI = dyn_cast<LoadInst>(I)) { - LoadInst *LJ = cast<LoadInst>(J); - IPtr = LI->getPointerOperand(); - JPtr = LJ->getPointerOperand(); - IAlignment = LI->getAlignment(); - JAlignment = LJ->getAlignment(); - IAddressSpace = LI->getPointerAddressSpace(); - JAddressSpace = LJ->getPointerAddressSpace(); - } else { - StoreInst *SI = cast<StoreInst>(I), *SJ = cast<StoreInst>(J); - IPtr = SI->getPointerOperand(); - JPtr = SJ->getPointerOperand(); - IAlignment = SI->getAlignment(); - JAlignment = SJ->getAlignment(); - IAddressSpace = SI->getPointerAddressSpace(); - JAddressSpace = SJ->getPointerAddressSpace(); - } - - if (!ComputeOffset) - return true; - - const SCEV *IPtrSCEV = SE->getSCEV(IPtr); - const SCEV *JPtrSCEV = SE->getSCEV(JPtr); - - // If this is a trivial offset, then we'll get something like - // 1*sizeof(type). With target data, which we need anyway, this will get - // constant folded into a number. - const SCEV *OffsetSCEV = SE->getMinusSCEV(JPtrSCEV, IPtrSCEV); - if (const SCEVConstant *ConstOffSCEV = - dyn_cast<SCEVConstant>(OffsetSCEV)) { - ConstantInt *IntOff = ConstOffSCEV->getValue(); - int64_t Offset = IntOff->getSExtValue(); - const DataLayout &DL = I->getModule()->getDataLayout(); - Type *VTy = IPtr->getType()->getPointerElementType(); - int64_t VTyTSS = (int64_t)DL.getTypeStoreSize(VTy); - - Type *VTy2 = JPtr->getType()->getPointerElementType(); - if (VTy != VTy2 && Offset < 0) { - int64_t VTy2TSS = (int64_t)DL.getTypeStoreSize(VTy2); - OffsetInElmts = Offset/VTy2TSS; - return (std::abs(Offset) % VTy2TSS) == 0; - } - - OffsetInElmts = Offset/VTyTSS; - return (std::abs(Offset) % VTyTSS) == 0; - } - - return false; - } - - // Returns true if the provided CallInst represents an intrinsic that can - // be vectorized. - bool isVectorizableIntrinsic(CallInst* I) { - Function *F = I->getCalledFunction(); - if (!F) return false; - - Intrinsic::ID IID = F->getIntrinsicID(); - if (!IID) return false; - - switch(IID) { - default: - return false; - case Intrinsic::sqrt: - case Intrinsic::powi: - case Intrinsic::sin: - case Intrinsic::cos: - case Intrinsic::log: - case Intrinsic::log2: - case Intrinsic::log10: - case Intrinsic::exp: - case Intrinsic::exp2: - case Intrinsic::pow: - case Intrinsic::round: - case Intrinsic::copysign: - case Intrinsic::ceil: - case Intrinsic::nearbyint: - case Intrinsic::rint: - case Intrinsic::trunc: - case Intrinsic::floor: - case Intrinsic::fabs: - case Intrinsic::minnum: - case Intrinsic::maxnum: - return Config.VectorizeMath; - case Intrinsic::bswap: - case Intrinsic::ctpop: - case Intrinsic::ctlz: - case Intrinsic::cttz: - return Config.VectorizeBitManipulations; - case Intrinsic::fma: - case Intrinsic::fmuladd: - return Config.VectorizeFMA; - } - } - - bool isPureIEChain(InsertElementInst *IE) { - InsertElementInst *IENext = IE; - do { - if (!isa<UndefValue>(IENext->getOperand(0)) && - !isa<InsertElementInst>(IENext->getOperand(0))) { - return false; - } - } while ((IENext = - dyn_cast<InsertElementInst>(IENext->getOperand(0)))); - - return true; - } - }; - - // This function implements one vectorization iteration on the provided - // basic block. It returns true if the block is changed. - bool BBVectorize::vectorizePairs(BasicBlock &BB, bool NonPow2Len) { - bool ShouldContinue; - BasicBlock::iterator Start = BB.getFirstInsertionPt(); - - std::vector<Value *> AllPairableInsts; - DenseMap<Value *, Value *> AllChosenPairs; - DenseSet<ValuePair> AllFixedOrderPairs; - DenseMap<VPPair, unsigned> AllPairConnectionTypes; - DenseMap<ValuePair, std::vector<ValuePair> > AllConnectedPairs, - AllConnectedPairDeps; - - do { - std::vector<Value *> PairableInsts; - DenseMap<Value *, std::vector<Value *> > CandidatePairs; - DenseSet<ValuePair> FixedOrderPairs; - DenseMap<ValuePair, int> CandidatePairCostSavings; - ShouldContinue = getCandidatePairs(BB, Start, CandidatePairs, - FixedOrderPairs, - CandidatePairCostSavings, - PairableInsts, NonPow2Len); - if (PairableInsts.empty()) continue; - - // Build the candidate pair set for faster lookups. - DenseSet<ValuePair> CandidatePairsSet; - for (DenseMap<Value *, std::vector<Value *> >::iterator I = - CandidatePairs.begin(), E = CandidatePairs.end(); I != E; ++I) - for (std::vector<Value *>::iterator J = I->second.begin(), - JE = I->second.end(); J != JE; ++J) - CandidatePairsSet.insert(ValuePair(I->first, *J)); - - // Now we have a map of all of the pairable instructions and we need to - // select the best possible pairing. A good pairing is one such that the - // users of the pair are also paired. This defines a (directed) forest - // over the pairs such that two pairs are connected iff the second pair - // uses the first. - - // Note that it only matters that both members of the second pair use some - // element of the first pair (to allow for splatting). - - DenseMap<ValuePair, std::vector<ValuePair> > ConnectedPairs, - ConnectedPairDeps; - DenseMap<VPPair, unsigned> PairConnectionTypes; - computeConnectedPairs(CandidatePairs, CandidatePairsSet, - PairableInsts, ConnectedPairs, PairConnectionTypes); - if (ConnectedPairs.empty()) continue; - - for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator - I = ConnectedPairs.begin(), IE = ConnectedPairs.end(); - I != IE; ++I) - for (std::vector<ValuePair>::iterator J = I->second.begin(), - JE = I->second.end(); J != JE; ++J) - ConnectedPairDeps[*J].push_back(I->first); - - // Build the pairable-instruction dependency map - DenseSet<ValuePair> PairableInstUsers; - buildDepMap(BB, CandidatePairs, PairableInsts, PairableInstUsers); - - // There is now a graph of the connected pairs. For each variable, pick - // the pairing with the largest dag meeting the depth requirement on at - // least one branch. Then select all pairings that are part of that dag - // and remove them from the list of available pairings and pairable - // variables. - - DenseMap<Value *, Value *> ChosenPairs; - choosePairs(CandidatePairs, CandidatePairsSet, - CandidatePairCostSavings, - PairableInsts, FixedOrderPairs, PairConnectionTypes, - ConnectedPairs, ConnectedPairDeps, - PairableInstUsers, ChosenPairs); - - if (ChosenPairs.empty()) continue; - AllPairableInsts.insert(AllPairableInsts.end(), PairableInsts.begin(), - PairableInsts.end()); - AllChosenPairs.insert(ChosenPairs.begin(), ChosenPairs.end()); - - // Only for the chosen pairs, propagate information on fixed-order pairs, - // pair connections, and their types to the data structures used by the - // pair fusion procedures. - for (DenseMap<Value *, Value *>::iterator I = ChosenPairs.begin(), - IE = ChosenPairs.end(); I != IE; ++I) { - if (FixedOrderPairs.count(*I)) - AllFixedOrderPairs.insert(*I); - else if (FixedOrderPairs.count(ValuePair(I->second, I->first))) - AllFixedOrderPairs.insert(ValuePair(I->second, I->first)); - - for (DenseMap<Value *, Value *>::iterator J = ChosenPairs.begin(); - J != IE; ++J) { - DenseMap<VPPair, unsigned>::iterator K = - PairConnectionTypes.find(VPPair(*I, *J)); - if (K != PairConnectionTypes.end()) { - AllPairConnectionTypes.insert(*K); - } else { - K = PairConnectionTypes.find(VPPair(*J, *I)); - if (K != PairConnectionTypes.end()) - AllPairConnectionTypes.insert(*K); - } - } - } - - for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator - I = ConnectedPairs.begin(), IE = ConnectedPairs.end(); - I != IE; ++I) - for (std::vector<ValuePair>::iterator J = I->second.begin(), - JE = I->second.end(); J != JE; ++J) - if (AllPairConnectionTypes.count(VPPair(I->first, *J))) { - AllConnectedPairs[I->first].push_back(*J); - AllConnectedPairDeps[*J].push_back(I->first); - } - } while (ShouldContinue); - - if (AllChosenPairs.empty()) return false; - NumFusedOps += AllChosenPairs.size(); - - // A set of pairs has now been selected. It is now necessary to replace the - // paired instructions with vector instructions. For this procedure each - // operand must be replaced with a vector operand. This vector is formed - // by using build_vector on the old operands. The replaced values are then - // replaced with a vector_extract on the result. Subsequent optimization - // passes should coalesce the build/extract combinations. - - fuseChosenPairs(BB, AllPairableInsts, AllChosenPairs, AllFixedOrderPairs, - AllPairConnectionTypes, - AllConnectedPairs, AllConnectedPairDeps); - - // It is important to cleanup here so that future iterations of this - // function have less work to do. - (void)SimplifyInstructionsInBlock(&BB, TLI); - return true; - } - - // This function returns true if the provided instruction is capable of being - // fused into a vector instruction. This determination is based only on the - // type and other attributes of the instruction. - bool BBVectorize::isInstVectorizable(Instruction *I, - bool &IsSimpleLoadStore) { - IsSimpleLoadStore = false; - - if (CallInst *C = dyn_cast<CallInst>(I)) { - if (!isVectorizableIntrinsic(C)) - return false; - } else if (LoadInst *L = dyn_cast<LoadInst>(I)) { - // Vectorize simple loads if possbile: - IsSimpleLoadStore = L->isSimple(); - if (!IsSimpleLoadStore || !Config.VectorizeMemOps) - return false; - } else if (StoreInst *S = dyn_cast<StoreInst>(I)) { - // Vectorize simple stores if possbile: - IsSimpleLoadStore = S->isSimple(); - if (!IsSimpleLoadStore || !Config.VectorizeMemOps) - return false; - } else if (CastInst *C = dyn_cast<CastInst>(I)) { - // We can vectorize casts, but not casts of pointer types, etc. - if (!Config.VectorizeCasts) - return false; - - Type *SrcTy = C->getSrcTy(); - if (!SrcTy->isSingleValueType()) - return false; - - Type *DestTy = C->getDestTy(); - if (!DestTy->isSingleValueType()) - return false; - } else if (SelectInst *SI = dyn_cast<SelectInst>(I)) { - if (!Config.VectorizeSelect) - return false; - // We can vectorize a select if either all operands are scalars, - // or all operands are vectors. Trying to "widen" a select between - // vectors that has a scalar condition results in a malformed select. - // FIXME: We could probably be smarter about this by rewriting the select - // with different types instead. - return (SI->getCondition()->getType()->isVectorTy() == - SI->getTrueValue()->getType()->isVectorTy()); - } else if (isa<CmpInst>(I)) { - if (!Config.VectorizeCmp) - return false; - } else if (GetElementPtrInst *G = dyn_cast<GetElementPtrInst>(I)) { - if (!Config.VectorizeGEP) - return false; - - // Currently, vector GEPs exist only with one index. - if (G->getNumIndices() != 1) - return false; - } else if (!(I->isBinaryOp() || isa<ShuffleVectorInst>(I) || - isa<ExtractElementInst>(I) || isa<InsertElementInst>(I))) { - return false; - } - - Type *T1, *T2; - getInstructionTypes(I, T1, T2); - - // Not every type can be vectorized... - if (!(VectorType::isValidElementType(T1) || T1->isVectorTy()) || - !(VectorType::isValidElementType(T2) || T2->isVectorTy())) - return false; - - if (T1->getScalarSizeInBits() == 1) { - if (!Config.VectorizeBools) - return false; - } else { - if (!Config.VectorizeInts && T1->isIntOrIntVectorTy()) - return false; - } - - if (T2->getScalarSizeInBits() == 1) { - if (!Config.VectorizeBools) - return false; - } else { - if (!Config.VectorizeInts && T2->isIntOrIntVectorTy()) - return false; - } - - if (!Config.VectorizeFloats - && (T1->isFPOrFPVectorTy() || T2->isFPOrFPVectorTy())) - return false; - - // Don't vectorize target-specific types. - if (T1->isX86_FP80Ty() || T1->isPPC_FP128Ty() || T1->isX86_MMXTy()) - return false; - if (T2->isX86_FP80Ty() || T2->isPPC_FP128Ty() || T2->isX86_MMXTy()) - return false; - - if (!Config.VectorizePointers && (T1->getScalarType()->isPointerTy() || - T2->getScalarType()->isPointerTy())) - return false; - - if (!TTI && (T1->getPrimitiveSizeInBits() >= Config.VectorBits || - T2->getPrimitiveSizeInBits() >= Config.VectorBits)) - return false; - - return true; - } - - // This function returns true if the two provided instructions are compatible - // (meaning that they can be fused into a vector instruction). This assumes - // that I has already been determined to be vectorizable and that J is not - // in the use dag of I. - bool BBVectorize::areInstsCompatible(Instruction *I, Instruction *J, - bool IsSimpleLoadStore, bool NonPow2Len, - int &CostSavings, int &FixedOrder) { - DEBUG(if (DebugInstructionExamination) dbgs() << "BBV: looking at " << *I << - " <-> " << *J << "\n"); - - CostSavings = 0; - FixedOrder = 0; - - // Loads and stores can be merged if they have different alignments, - // but are otherwise the same. - if (!J->isSameOperationAs(I, Instruction::CompareIgnoringAlignment | - (NonPow2Len ? Instruction::CompareUsingScalarTypes : 0))) - return false; - - Type *IT1, *IT2, *JT1, *JT2; - getInstructionTypes(I, IT1, IT2); - getInstructionTypes(J, JT1, JT2); - unsigned MaxTypeBits = std::max( - IT1->getPrimitiveSizeInBits() + JT1->getPrimitiveSizeInBits(), - IT2->getPrimitiveSizeInBits() + JT2->getPrimitiveSizeInBits()); - if (!TTI && MaxTypeBits > Config.VectorBits) - return false; - - // FIXME: handle addsub-type operations! - - if (IsSimpleLoadStore) { - Value *IPtr, *JPtr; - unsigned IAlignment, JAlignment, IAddressSpace, JAddressSpace; - int64_t OffsetInElmts = 0; - if (getPairPtrInfo(I, J, IPtr, JPtr, IAlignment, JAlignment, - IAddressSpace, JAddressSpace, OffsetInElmts) && - std::abs(OffsetInElmts) == 1) { - FixedOrder = (int) OffsetInElmts; - unsigned BottomAlignment = IAlignment; - if (OffsetInElmts < 0) BottomAlignment = JAlignment; - - Type *aTypeI = isa<StoreInst>(I) ? - cast<StoreInst>(I)->getValueOperand()->getType() : I->getType(); - Type *aTypeJ = isa<StoreInst>(J) ? - cast<StoreInst>(J)->getValueOperand()->getType() : J->getType(); - Type *VType = getVecTypeForPair(aTypeI, aTypeJ); - - if (Config.AlignedOnly) { - // An aligned load or store is possible only if the instruction - // with the lower offset has an alignment suitable for the - // vector type. - const DataLayout &DL = I->getModule()->getDataLayout(); - unsigned VecAlignment = DL.getPrefTypeAlignment(VType); - if (BottomAlignment < VecAlignment) - return false; - } - - if (TTI) { - unsigned ICost = TTI->getMemoryOpCost(I->getOpcode(), aTypeI, - IAlignment, IAddressSpace); - unsigned JCost = TTI->getMemoryOpCost(J->getOpcode(), aTypeJ, - JAlignment, JAddressSpace); - unsigned VCost = TTI->getMemoryOpCost(I->getOpcode(), VType, - BottomAlignment, - IAddressSpace); - - ICost += TTI->getAddressComputationCost(aTypeI); - JCost += TTI->getAddressComputationCost(aTypeJ); - VCost += TTI->getAddressComputationCost(VType); - - if (VCost > ICost + JCost) - return false; - - // We don't want to fuse to a type that will be split, even - // if the two input types will also be split and there is no other - // associated cost. - unsigned VParts = TTI->getNumberOfParts(VType); - if (VParts > 1) - return false; - else if (!VParts && VCost == ICost + JCost) - return false; - - CostSavings = ICost + JCost - VCost; - } - } else { - return false; - } - } else if (TTI) { - TargetTransformInfo::OperandValueKind Op1VK = - TargetTransformInfo::OK_AnyValue; - TargetTransformInfo::OperandValueKind Op2VK = - TargetTransformInfo::OK_AnyValue; - unsigned ICost = getInstrCost(I->getOpcode(), IT1, IT2, Op1VK, Op2VK, I); - unsigned JCost = getInstrCost(J->getOpcode(), JT1, JT2, Op1VK, Op2VK, J); - Type *VT1 = getVecTypeForPair(IT1, JT1), - *VT2 = getVecTypeForPair(IT2, JT2); - - // On some targets (example X86) the cost of a vector shift may vary - // depending on whether the second operand is a Uniform or - // NonUniform Constant. - switch (I->getOpcode()) { - default : break; - case Instruction::Shl: - case Instruction::LShr: - case Instruction::AShr: - - // If both I and J are scalar shifts by constant, then the - // merged vector shift count would be either a constant splat value - // or a non-uniform vector of constants. - if (ConstantInt *CII = dyn_cast<ConstantInt>(I->getOperand(1))) { - if (ConstantInt *CIJ = dyn_cast<ConstantInt>(J->getOperand(1))) - Op2VK = CII == CIJ ? TargetTransformInfo::OK_UniformConstantValue : - TargetTransformInfo::OK_NonUniformConstantValue; - } else { - // Check for a splat of a constant or for a non uniform vector - // of constants. - Value *IOp = I->getOperand(1); - Value *JOp = J->getOperand(1); - if ((isa<ConstantVector>(IOp) || isa<ConstantDataVector>(IOp)) && - (isa<ConstantVector>(JOp) || isa<ConstantDataVector>(JOp))) { - Op2VK = TargetTransformInfo::OK_NonUniformConstantValue; - Constant *SplatValue = cast<Constant>(IOp)->getSplatValue(); - if (SplatValue != nullptr && - SplatValue == cast<Constant>(JOp)->getSplatValue()) - Op2VK = TargetTransformInfo::OK_UniformConstantValue; - } - } - } - - // Note that this procedure is incorrect for insert and extract element - // instructions (because combining these often results in a shuffle), - // but this cost is ignored (because insert and extract element - // instructions are assigned a zero depth factor and are not really - // fused in general). - unsigned VCost = getInstrCost(I->getOpcode(), VT1, VT2, Op1VK, Op2VK, I); - - if (VCost > ICost + JCost) - return false; - - // We don't want to fuse to a type that will be split, even - // if the two input types will also be split and there is no other - // associated cost. - unsigned VParts1 = TTI->getNumberOfParts(VT1), - VParts2 = TTI->getNumberOfParts(VT2); - if (VParts1 > 1 || VParts2 > 1) - return false; - else if ((!VParts1 || !VParts2) && VCost == ICost + JCost) - return false; - - CostSavings = ICost + JCost - VCost; - } - - // The powi,ctlz,cttz intrinsics are special because only the first - // argument is vectorized, the second arguments must be equal. - CallInst *CI = dyn_cast<CallInst>(I); - Function *FI; - if (CI && (FI = CI->getCalledFunction())) { - Intrinsic::ID IID = FI->getIntrinsicID(); - if (IID == Intrinsic::powi || IID == Intrinsic::ctlz || - IID == Intrinsic::cttz) { - Value *A1I = CI->getArgOperand(1), - *A1J = cast<CallInst>(J)->getArgOperand(1); - const SCEV *A1ISCEV = SE->getSCEV(A1I), - *A1JSCEV = SE->getSCEV(A1J); - return (A1ISCEV == A1JSCEV); - } - - if (IID && TTI) { - FastMathFlags FMFCI; - if (auto *FPMOCI = dyn_cast<FPMathOperator>(CI)) - FMFCI = FPMOCI->getFastMathFlags(); - SmallVector<Value *, 4> IArgs(CI->arg_operands()); - unsigned ICost = TTI->getIntrinsicInstrCost(IID, IT1, IArgs, FMFCI); - - CallInst *CJ = cast<CallInst>(J); - - FastMathFlags FMFCJ; - if (auto *FPMOCJ = dyn_cast<FPMathOperator>(CJ)) - FMFCJ = FPMOCJ->getFastMathFlags(); - - SmallVector<Value *, 4> JArgs(CJ->arg_operands()); - unsigned JCost = TTI->getIntrinsicInstrCost(IID, JT1, JArgs, FMFCJ); - - assert(CI->getNumArgOperands() == CJ->getNumArgOperands() && - "Intrinsic argument counts differ"); - SmallVector<Type*, 4> Tys; - SmallVector<Value *, 4> VecArgs; - for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) { - if ((IID == Intrinsic::powi || IID == Intrinsic::ctlz || - IID == Intrinsic::cttz) && i == 1) { - Tys.push_back(CI->getArgOperand(i)->getType()); - VecArgs.push_back(CI->getArgOperand(i)); - } - else { - Tys.push_back(getVecTypeForPair(CI->getArgOperand(i)->getType(), - CJ->getArgOperand(i)->getType())); - // Add both operands, and then count their scalarization overhead - // with VF 1. - VecArgs.push_back(CI->getArgOperand(i)); - VecArgs.push_back(CJ->getArgOperand(i)); - } - } - - // Compute the scalarization cost here with the original operands (to - // check for uniqueness etc), and then call getIntrinsicInstrCost() - // with the constructed vector types. - Type *RetTy = getVecTypeForPair(IT1, JT1); - unsigned ScalarizationCost = 0; - if (!RetTy->isVoidTy()) - ScalarizationCost += TTI->getScalarizationOverhead(RetTy, true, false); - ScalarizationCost += TTI->getOperandsScalarizationOverhead(VecArgs, 1); - - FastMathFlags FMFV = FMFCI; - FMFV &= FMFCJ; - unsigned VCost = TTI->getIntrinsicInstrCost(IID, RetTy, Tys, FMFV, - ScalarizationCost); - - if (VCost > ICost + JCost) - return false; - - // We don't want to fuse to a type that will be split, even - // if the two input types will also be split and there is no other - // associated cost. - unsigned RetParts = TTI->getNumberOfParts(RetTy); - if (RetParts > 1) - return false; - else if (!RetParts && VCost == ICost + JCost) - return false; - - for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) { - if (!Tys[i]->isVectorTy()) - continue; - - unsigned NumParts = TTI->getNumberOfParts(Tys[i]); - if (NumParts > 1) - return false; - else if (!NumParts && VCost == ICost + JCost) - return false; - } - - CostSavings = ICost + JCost - VCost; - } - } - - return true; - } - - // Figure out whether or not J uses I and update the users and write-set - // structures associated with I. Specifically, Users represents the set of - // instructions that depend on I. WriteSet represents the set - // of memory locations that are dependent on I. If UpdateUsers is true, - // and J uses I, then Users is updated to contain J and WriteSet is updated - // to contain any memory locations to which J writes. The function returns - // true if J uses I. By default, alias analysis is used to determine - // whether J reads from memory that overlaps with a location in WriteSet. - // If LoadMoveSet is not null, then it is a previously-computed map - // where the key is the memory-based user instruction and the value is - // the instruction to be compared with I. So, if LoadMoveSet is provided, - // then the alias analysis is not used. This is necessary because this - // function is called during the process of moving instructions during - // vectorization and the results of the alias analysis are not stable during - // that process. - bool BBVectorize::trackUsesOfI(DenseSet<Value *> &Users, - AliasSetTracker &WriteSet, Instruction *I, - Instruction *J, bool UpdateUsers, - DenseSet<ValuePair> *LoadMoveSetPairs) { - bool UsesI = false; - - // This instruction may already be marked as a user due, for example, to - // being a member of a selected pair. - if (Users.count(J)) - UsesI = true; - - if (!UsesI) - for (User::op_iterator JU = J->op_begin(), JE = J->op_end(); - JU != JE; ++JU) { - Value *V = *JU; - if (I == V || Users.count(V)) { - UsesI = true; - break; - } - } - if (!UsesI && J->mayReadFromMemory()) { - if (LoadMoveSetPairs) { - UsesI = LoadMoveSetPairs->count(ValuePair(J, I)); - } else { - for (AliasSetTracker::iterator W = WriteSet.begin(), - WE = WriteSet.end(); W != WE; ++W) { - if (W->aliasesUnknownInst(J, *AA)) { - UsesI = true; - break; - } - } - } - } - - if (UsesI && UpdateUsers) { - if (J->mayWriteToMemory()) WriteSet.add(J); - Users.insert(J); - } - - return UsesI; - } - - // This function iterates over all instruction pairs in the provided - // basic block and collects all candidate pairs for vectorization. - bool BBVectorize::getCandidatePairs(BasicBlock &BB, - BasicBlock::iterator &Start, - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<ValuePair, int> &CandidatePairCostSavings, - std::vector<Value *> &PairableInsts, bool NonPow2Len) { - size_t TotalPairs = 0; - BasicBlock::iterator E = BB.end(); - if (Start == E) return false; - - bool ShouldContinue = false, IAfterStart = false; - for (BasicBlock::iterator I = Start++; I != E; ++I) { - if (I == Start) IAfterStart = true; - - bool IsSimpleLoadStore; - if (!isInstVectorizable(&*I, IsSimpleLoadStore)) - continue; - - // Look for an instruction with which to pair instruction *I... - DenseSet<Value *> Users; - AliasSetTracker WriteSet(*AA); - if (I->mayWriteToMemory()) - WriteSet.add(&*I); - - bool JAfterStart = IAfterStart; - BasicBlock::iterator J = std::next(I); - for (unsigned ss = 0; J != E && ss <= Config.SearchLimit; ++J, ++ss) { - if (J == Start) - JAfterStart = true; - - // Determine if J uses I, if so, exit the loop. - bool UsesI = trackUsesOfI(Users, WriteSet, &*I, &*J, !Config.FastDep); - if (Config.FastDep) { - // Note: For this heuristic to be effective, independent operations - // must tend to be intermixed. This is likely to be true from some - // kinds of grouped loop unrolling (but not the generic LLVM pass), - // but otherwise may require some kind of reordering pass. - - // When using fast dependency analysis, - // stop searching after first use: - if (UsesI) break; - } else { - if (UsesI) continue; - } - - // J does not use I, and comes before the first use of I, so it can be - // merged with I if the instructions are compatible. - int CostSavings, FixedOrder; - if (!areInstsCompatible(&*I, &*J, IsSimpleLoadStore, NonPow2Len, - CostSavings, FixedOrder)) - continue; - - // J is a candidate for merging with I. - if (PairableInsts.empty() || - PairableInsts[PairableInsts.size() - 1] != &*I) { - PairableInsts.push_back(&*I); - } - - CandidatePairs[&*I].push_back(&*J); - ++TotalPairs; - if (TTI) - CandidatePairCostSavings.insert( - ValuePairWithCost(ValuePair(&*I, &*J), CostSavings)); - - if (FixedOrder == 1) - FixedOrderPairs.insert(ValuePair(&*I, &*J)); - else if (FixedOrder == -1) - FixedOrderPairs.insert(ValuePair(&*J, &*I)); - - // The next call to this function must start after the last instruction - // selected during this invocation. - if (JAfterStart) { - Start = std::next(J); - IAfterStart = JAfterStart = false; - } - - DEBUG(if (DebugCandidateSelection) dbgs() << "BBV: candidate pair " - << *I << " <-> " << *J << " (cost savings: " << - CostSavings << ")\n"); - - // If we have already found too many pairs, break here and this function - // will be called again starting after the last instruction selected - // during this invocation. - if (PairableInsts.size() >= Config.MaxInsts || - TotalPairs >= Config.MaxPairs) { - ShouldContinue = true; - break; - } - } - - if (ShouldContinue) - break; - } - - DEBUG(dbgs() << "BBV: found " << PairableInsts.size() - << " instructions with candidate pairs\n"); - - return ShouldContinue; - } - - // Finds candidate pairs connected to the pair P = <PI, PJ>. This means that - // it looks for pairs such that both members have an input which is an - // output of PI or PJ. - void BBVectorize::computePairsConnectedTo( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - ValuePair P) { - StoreInst *SI, *SJ; - - // For each possible pairing for this variable, look at the uses of - // the first value... - for (Value::user_iterator I = P.first->user_begin(), - E = P.first->user_end(); - I != E; ++I) { - User *UI = *I; - if (isa<LoadInst>(UI)) { - // A pair cannot be connected to a load because the load only takes one - // operand (the address) and it is a scalar even after vectorization. - continue; - } else if ((SI = dyn_cast<StoreInst>(UI)) && - P.first == SI->getPointerOperand()) { - // Similarly, a pair cannot be connected to a store through its - // pointer operand. - continue; - } - - // For each use of the first variable, look for uses of the second - // variable... - for (User *UJ : P.second->users()) { - if ((SJ = dyn_cast<StoreInst>(UJ)) && - P.second == SJ->getPointerOperand()) - continue; - - // Look for <I, J>: - if (CandidatePairsSet.count(ValuePair(UI, UJ))) { - VPPair VP(P, ValuePair(UI, UJ)); - ConnectedPairs[VP.first].push_back(VP.second); - PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionDirect)); - } - - // Look for <J, I>: - if (CandidatePairsSet.count(ValuePair(UJ, UI))) { - VPPair VP(P, ValuePair(UJ, UI)); - ConnectedPairs[VP.first].push_back(VP.second); - PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSwap)); - } - } - - if (Config.SplatBreaksChain) continue; - // Look for cases where just the first value in the pair is used by - // both members of another pair (splatting). - for (Value::user_iterator J = P.first->user_begin(); J != E; ++J) { - User *UJ = *J; - if ((SJ = dyn_cast<StoreInst>(UJ)) && - P.first == SJ->getPointerOperand()) - continue; - - if (CandidatePairsSet.count(ValuePair(UI, UJ))) { - VPPair VP(P, ValuePair(UI, UJ)); - ConnectedPairs[VP.first].push_back(VP.second); - PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSplat)); - } - } - } - - if (Config.SplatBreaksChain) return; - // Look for cases where just the second value in the pair is used by - // both members of another pair (splatting). - for (Value::user_iterator I = P.second->user_begin(), - E = P.second->user_end(); - I != E; ++I) { - User *UI = *I; - if (isa<LoadInst>(UI)) - continue; - else if ((SI = dyn_cast<StoreInst>(UI)) && - P.second == SI->getPointerOperand()) - continue; - - for (Value::user_iterator J = P.second->user_begin(); J != E; ++J) { - User *UJ = *J; - if ((SJ = dyn_cast<StoreInst>(UJ)) && - P.second == SJ->getPointerOperand()) - continue; - - if (CandidatePairsSet.count(ValuePair(UI, UJ))) { - VPPair VP(P, ValuePair(UI, UJ)); - ConnectedPairs[VP.first].push_back(VP.second); - PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSplat)); - } - } - } - } - - // This function figures out which pairs are connected. Two pairs are - // connected if some output of the first pair forms an input to both members - // of the second pair. - void BBVectorize::computeConnectedPairs( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes) { - for (std::vector<Value *>::iterator PI = PairableInsts.begin(), - PE = PairableInsts.end(); PI != PE; ++PI) { - DenseMap<Value *, std::vector<Value *> >::iterator PP = - CandidatePairs.find(*PI); - if (PP == CandidatePairs.end()) - continue; - - for (std::vector<Value *>::iterator P = PP->second.begin(), - E = PP->second.end(); P != E; ++P) - computePairsConnectedTo(CandidatePairs, CandidatePairsSet, - PairableInsts, ConnectedPairs, - PairConnectionTypes, ValuePair(*PI, *P)); - } - - DEBUG(size_t TotalPairs = 0; - for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator I = - ConnectedPairs.begin(), IE = ConnectedPairs.end(); I != IE; ++I) - TotalPairs += I->second.size(); - dbgs() << "BBV: found " << TotalPairs - << " pair connections.\n"); - } - - // This function builds a set of use tuples such that <A, B> is in the set - // if B is in the use dag of A. If B is in the use dag of A, then B - // depends on the output of A. - void BBVectorize::buildDepMap( - BasicBlock &BB, - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - std::vector<Value *> &PairableInsts, - DenseSet<ValuePair> &PairableInstUsers) { - DenseSet<Value *> IsInPair; - for (DenseMap<Value *, std::vector<Value *> >::iterator C = - CandidatePairs.begin(), E = CandidatePairs.end(); C != E; ++C) { - IsInPair.insert(C->first); - IsInPair.insert(C->second.begin(), C->second.end()); - } - - // Iterate through the basic block, recording all users of each - // pairable instruction. - - BasicBlock::iterator E = BB.end(), EL = - BasicBlock::iterator(cast<Instruction>(PairableInsts.back())); - for (BasicBlock::iterator I = BB.getFirstInsertionPt(); I != E; ++I) { - if (IsInPair.find(&*I) == IsInPair.end()) - continue; - - DenseSet<Value *> Users; - AliasSetTracker WriteSet(*AA); - if (I->mayWriteToMemory()) - WriteSet.add(&*I); - - for (BasicBlock::iterator J = std::next(I); J != E; ++J) { - (void)trackUsesOfI(Users, WriteSet, &*I, &*J); - - if (J == EL) - break; - } - - for (DenseSet<Value *>::iterator U = Users.begin(), E = Users.end(); - U != E; ++U) { - if (IsInPair.find(*U) == IsInPair.end()) continue; - PairableInstUsers.insert(ValuePair(&*I, *U)); - } - - if (I == EL) - break; - } - } - - // Returns true if an input to pair P is an output of pair Q and also an - // input of pair Q is an output of pair P. If this is the case, then these - // two pairs cannot be simultaneously fused. - bool BBVectorize::pairsConflict(ValuePair P, ValuePair Q, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<ValuePair, std::vector<ValuePair> > *PairableInstUserMap, - DenseSet<VPPair> *PairableInstUserPairSet) { - // Two pairs are in conflict if they are mutual Users of eachother. - bool QUsesP = PairableInstUsers.count(ValuePair(P.first, Q.first)) || - PairableInstUsers.count(ValuePair(P.first, Q.second)) || - PairableInstUsers.count(ValuePair(P.second, Q.first)) || - PairableInstUsers.count(ValuePair(P.second, Q.second)); - bool PUsesQ = PairableInstUsers.count(ValuePair(Q.first, P.first)) || - PairableInstUsers.count(ValuePair(Q.first, P.second)) || - PairableInstUsers.count(ValuePair(Q.second, P.first)) || - PairableInstUsers.count(ValuePair(Q.second, P.second)); - if (PairableInstUserMap) { - // FIXME: The expensive part of the cycle check is not so much the cycle - // check itself but this edge insertion procedure. This needs some - // profiling and probably a different data structure. - if (PUsesQ) { - if (PairableInstUserPairSet->insert(VPPair(Q, P)).second) - (*PairableInstUserMap)[Q].push_back(P); - } - if (QUsesP) { - if (PairableInstUserPairSet->insert(VPPair(P, Q)).second) - (*PairableInstUserMap)[P].push_back(Q); - } - } - - return (QUsesP && PUsesQ); - } - - // This function walks the use graph of current pairs to see if, starting - // from P, the walk returns to P. - bool BBVectorize::pairWillFormCycle(ValuePair P, - DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap, - DenseSet<ValuePair> &CurrentPairs) { - DEBUG(if (DebugCycleCheck) - dbgs() << "BBV: starting cycle check for : " << *P.first << " <-> " - << *P.second << "\n"); - // A lookup table of visisted pairs is kept because the PairableInstUserMap - // contains non-direct associations. - DenseSet<ValuePair> Visited; - SmallVector<ValuePair, 32> Q; - // General depth-first post-order traversal: - Q.push_back(P); - do { - ValuePair QTop = Q.pop_back_val(); - Visited.insert(QTop); - - DEBUG(if (DebugCycleCheck) - dbgs() << "BBV: cycle check visiting: " << *QTop.first << " <-> " - << *QTop.second << "\n"); - DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ = - PairableInstUserMap.find(QTop); - if (QQ == PairableInstUserMap.end()) - continue; - - for (std::vector<ValuePair>::iterator C = QQ->second.begin(), - CE = QQ->second.end(); C != CE; ++C) { - if (*C == P) { - DEBUG(dbgs() - << "BBV: rejected to prevent non-trivial cycle formation: " - << QTop.first << " <-> " << C->second << "\n"); - return true; - } - - if (CurrentPairs.count(*C) && !Visited.count(*C)) - Q.push_back(*C); - } - } while (!Q.empty()); - - return false; - } - - // This function builds the initial dag of connected pairs with the - // pair J at the root. - void BBVectorize::buildInitialDAGFor( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<ValuePair, size_t> &DAG, ValuePair J) { - // Each of these pairs is viewed as the root node of a DAG. The DAG - // is then walked (depth-first). As this happens, we keep track of - // the pairs that compose the DAG and the maximum depth of the DAG. - SmallVector<ValuePairWithDepth, 32> Q; - // General depth-first post-order traversal: - Q.push_back(ValuePairWithDepth(J, getDepthFactor(J.first))); - do { - ValuePairWithDepth QTop = Q.back(); - - // Push each child onto the queue: - bool MoreChildren = false; - size_t MaxChildDepth = QTop.second; - DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ = - ConnectedPairs.find(QTop.first); - if (QQ != ConnectedPairs.end()) - for (std::vector<ValuePair>::iterator k = QQ->second.begin(), - ke = QQ->second.end(); k != ke; ++k) { - // Make sure that this child pair is still a candidate: - if (CandidatePairsSet.count(*k)) { - DenseMap<ValuePair, size_t>::iterator C = DAG.find(*k); - if (C == DAG.end()) { - size_t d = getDepthFactor(k->first); - Q.push_back(ValuePairWithDepth(*k, QTop.second+d)); - MoreChildren = true; - } else { - MaxChildDepth = std::max(MaxChildDepth, C->second); - } - } - } - - if (!MoreChildren) { - // Record the current pair as part of the DAG: - DAG.insert(ValuePairWithDepth(QTop.first, MaxChildDepth)); - Q.pop_back(); - } - } while (!Q.empty()); - } - - // Given some initial dag, prune it by removing conflicting pairs (pairs - // that cannot be simultaneously chosen for vectorization). - void BBVectorize::pruneDAGFor( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - std::vector<Value *> &PairableInsts, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap, - DenseSet<VPPair> &PairableInstUserPairSet, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<ValuePair, size_t> &DAG, - DenseSet<ValuePair> &PrunedDAG, ValuePair J, - bool UseCycleCheck) { - SmallVector<ValuePairWithDepth, 32> Q; - // General depth-first post-order traversal: - Q.push_back(ValuePairWithDepth(J, getDepthFactor(J.first))); - do { - ValuePairWithDepth QTop = Q.pop_back_val(); - PrunedDAG.insert(QTop.first); - - // Visit each child, pruning as necessary... - SmallVector<ValuePairWithDepth, 8> BestChildren; - DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ = - ConnectedPairs.find(QTop.first); - if (QQ == ConnectedPairs.end()) - continue; - - for (std::vector<ValuePair>::iterator K = QQ->second.begin(), - KE = QQ->second.end(); K != KE; ++K) { - DenseMap<ValuePair, size_t>::iterator C = DAG.find(*K); - if (C == DAG.end()) continue; - - // This child is in the DAG, now we need to make sure it is the - // best of any conflicting children. There could be multiple - // conflicting children, so first, determine if we're keeping - // this child, then delete conflicting children as necessary. - - // It is also necessary to guard against pairing-induced - // dependencies. Consider instructions a .. x .. y .. b - // such that (a,b) are to be fused and (x,y) are to be fused - // but a is an input to x and b is an output from y. This - // means that y cannot be moved after b but x must be moved - // after b for (a,b) to be fused. In other words, after - // fusing (a,b) we have y .. a/b .. x where y is an input - // to a/b and x is an output to a/b: x and y can no longer - // be legally fused. To prevent this condition, we must - // make sure that a child pair added to the DAG is not - // both an input and output of an already-selected pair. - - // Pairing-induced dependencies can also form from more complicated - // cycles. The pair vs. pair conflicts are easy to check, and so - // that is done explicitly for "fast rejection", and because for - // child vs. child conflicts, we may prefer to keep the current - // pair in preference to the already-selected child. - DenseSet<ValuePair> CurrentPairs; - - bool CanAdd = true; - for (SmallVectorImpl<ValuePairWithDepth>::iterator C2 - = BestChildren.begin(), E2 = BestChildren.end(); - C2 != E2; ++C2) { - if (C2->first.first == C->first.first || - C2->first.first == C->first.second || - C2->first.second == C->first.first || - C2->first.second == C->first.second || - pairsConflict(C2->first, C->first, PairableInstUsers, - UseCycleCheck ? &PairableInstUserMap : nullptr, - UseCycleCheck ? &PairableInstUserPairSet - : nullptr)) { - if (C2->second >= C->second) { - CanAdd = false; - break; - } - - CurrentPairs.insert(C2->first); - } - } - if (!CanAdd) continue; - - // Even worse, this child could conflict with another node already - // selected for the DAG. If that is the case, ignore this child. - for (DenseSet<ValuePair>::iterator T = PrunedDAG.begin(), - E2 = PrunedDAG.end(); T != E2; ++T) { - if (T->first == C->first.first || - T->first == C->first.second || - T->second == C->first.first || - T->second == C->first.second || - pairsConflict(*T, C->first, PairableInstUsers, - UseCycleCheck ? &PairableInstUserMap : nullptr, - UseCycleCheck ? &PairableInstUserPairSet - : nullptr)) { - CanAdd = false; - break; - } - - CurrentPairs.insert(*T); - } - if (!CanAdd) continue; - - // And check the queue too... - for (SmallVectorImpl<ValuePairWithDepth>::iterator C2 = Q.begin(), - E2 = Q.end(); C2 != E2; ++C2) { - if (C2->first.first == C->first.first || - C2->first.first == C->first.second || - C2->first.second == C->first.first || - C2->first.second == C->first.second || - pairsConflict(C2->first, C->first, PairableInstUsers, - UseCycleCheck ? &PairableInstUserMap : nullptr, - UseCycleCheck ? &PairableInstUserPairSet - : nullptr)) { - CanAdd = false; - break; - } - - CurrentPairs.insert(C2->first); - } - if (!CanAdd) continue; - - // Last but not least, check for a conflict with any of the - // already-chosen pairs. - for (DenseMap<Value *, Value *>::iterator C2 = - ChosenPairs.begin(), E2 = ChosenPairs.end(); - C2 != E2; ++C2) { - if (pairsConflict(*C2, C->first, PairableInstUsers, - UseCycleCheck ? &PairableInstUserMap : nullptr, - UseCycleCheck ? &PairableInstUserPairSet - : nullptr)) { - CanAdd = false; - break; - } - - CurrentPairs.insert(*C2); - } - if (!CanAdd) continue; - - // To check for non-trivial cycles formed by the addition of the - // current pair we've formed a list of all relevant pairs, now use a - // graph walk to check for a cycle. We start from the current pair and - // walk the use dag to see if we again reach the current pair. If we - // do, then the current pair is rejected. - - // FIXME: It may be more efficient to use a topological-ordering - // algorithm to improve the cycle check. This should be investigated. - if (UseCycleCheck && - pairWillFormCycle(C->first, PairableInstUserMap, CurrentPairs)) - continue; - - // This child can be added, but we may have chosen it in preference - // to an already-selected child. Check for this here, and if a - // conflict is found, then remove the previously-selected child - // before adding this one in its place. - for (SmallVectorImpl<ValuePairWithDepth>::iterator C2 - = BestChildren.begin(); C2 != BestChildren.end();) { - if (C2->first.first == C->first.first || - C2->first.first == C->first.second || - C2->first.second == C->first.first || - C2->first.second == C->first.second || - pairsConflict(C2->first, C->first, PairableInstUsers)) - C2 = BestChildren.erase(C2); - else - ++C2; - } - - BestChildren.push_back(ValuePairWithDepth(C->first, C->second)); - } - - for (SmallVectorImpl<ValuePairWithDepth>::iterator C - = BestChildren.begin(), E2 = BestChildren.end(); - C != E2; ++C) { - size_t DepthF = getDepthFactor(C->first.first); - Q.push_back(ValuePairWithDepth(C->first, QTop.second+DepthF)); - } - } while (!Q.empty()); - } - - // This function finds the best dag of mututally-compatible connected - // pairs, given the choice of root pairs as an iterator range. - void BBVectorize::findBestDAGFor( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - DenseMap<ValuePair, int> &CandidatePairCostSavings, - std::vector<Value *> &PairableInsts, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap, - DenseSet<VPPair> &PairableInstUserPairSet, - DenseMap<Value *, Value *> &ChosenPairs, - DenseSet<ValuePair> &BestDAG, size_t &BestMaxDepth, - int &BestEffSize, Value *II, std::vector<Value *>&JJ, - bool UseCycleCheck) { - for (std::vector<Value *>::iterator J = JJ.begin(), JE = JJ.end(); - J != JE; ++J) { - ValuePair IJ(II, *J); - if (!CandidatePairsSet.count(IJ)) - continue; - - // Before going any further, make sure that this pair does not - // conflict with any already-selected pairs (see comment below - // near the DAG pruning for more details). - DenseSet<ValuePair> ChosenPairSet; - bool DoesConflict = false; - for (DenseMap<Value *, Value *>::iterator C = ChosenPairs.begin(), - E = ChosenPairs.end(); C != E; ++C) { - if (pairsConflict(*C, IJ, PairableInstUsers, - UseCycleCheck ? &PairableInstUserMap : nullptr, - UseCycleCheck ? &PairableInstUserPairSet : nullptr)) { - DoesConflict = true; - break; - } - - ChosenPairSet.insert(*C); - } - if (DoesConflict) continue; - - if (UseCycleCheck && - pairWillFormCycle(IJ, PairableInstUserMap, ChosenPairSet)) - continue; - - DenseMap<ValuePair, size_t> DAG; - buildInitialDAGFor(CandidatePairs, CandidatePairsSet, - PairableInsts, ConnectedPairs, - PairableInstUsers, ChosenPairs, DAG, IJ); - - // Because we'll keep the child with the largest depth, the largest - // depth is still the same in the unpruned DAG. - size_t MaxDepth = DAG.lookup(IJ); - - DEBUG(if (DebugPairSelection) dbgs() << "BBV: found DAG for pair {" - << *IJ.first << " <-> " << *IJ.second << "} of depth " << - MaxDepth << " and size " << DAG.size() << "\n"); - - // At this point the DAG has been constructed, but, may contain - // contradictory children (meaning that different children of - // some dag node may be attempting to fuse the same instruction). - // So now we walk the dag again, in the case of a conflict, - // keep only the child with the largest depth. To break a tie, - // favor the first child. - - DenseSet<ValuePair> PrunedDAG; - pruneDAGFor(CandidatePairs, PairableInsts, ConnectedPairs, - PairableInstUsers, PairableInstUserMap, - PairableInstUserPairSet, - ChosenPairs, DAG, PrunedDAG, IJ, UseCycleCheck); - - int EffSize = 0; - if (TTI) { - DenseSet<Value *> PrunedDAGInstrs; - for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(), - E = PrunedDAG.end(); S != E; ++S) { - PrunedDAGInstrs.insert(S->first); - PrunedDAGInstrs.insert(S->second); - } - - // The set of pairs that have already contributed to the total cost. - DenseSet<ValuePair> IncomingPairs; - - // If the cost model were perfect, this might not be necessary; but we - // need to make sure that we don't get stuck vectorizing our own - // shuffle chains. - bool HasNontrivialInsts = false; - - // The node weights represent the cost savings associated with - // fusing the pair of instructions. - for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(), - E = PrunedDAG.end(); S != E; ++S) { - if (!isa<ShuffleVectorInst>(S->first) && - !isa<InsertElementInst>(S->first) && - !isa<ExtractElementInst>(S->first)) - HasNontrivialInsts = true; - - bool FlipOrder = false; - - if (getDepthFactor(S->first)) { - int ESContrib = CandidatePairCostSavings.find(*S)->second; - DEBUG(if (DebugPairSelection) dbgs() << "\tweight {" - << *S->first << " <-> " << *S->second << "} = " << - ESContrib << "\n"); - EffSize += ESContrib; - } - - // The edge weights contribute in a negative sense: they represent - // the cost of shuffles. - DenseMap<ValuePair, std::vector<ValuePair> >::iterator SS = - ConnectedPairDeps.find(*S); - if (SS != ConnectedPairDeps.end()) { - unsigned NumDepsDirect = 0, NumDepsSwap = 0; - for (std::vector<ValuePair>::iterator T = SS->second.begin(), - TE = SS->second.end(); T != TE; ++T) { - VPPair Q(*S, *T); - if (!PrunedDAG.count(Q.second)) - continue; - DenseMap<VPPair, unsigned>::iterator R = - PairConnectionTypes.find(VPPair(Q.second, Q.first)); - assert(R != PairConnectionTypes.end() && - "Cannot find pair connection type"); - if (R->second == PairConnectionDirect) - ++NumDepsDirect; - else if (R->second == PairConnectionSwap) - ++NumDepsSwap; - } - - // If there are more swaps than direct connections, then - // the pair order will be flipped during fusion. So the real - // number of swaps is the minimum number. - FlipOrder = !FixedOrderPairs.count(*S) && - ((NumDepsSwap > NumDepsDirect) || - FixedOrderPairs.count(ValuePair(S->second, S->first))); - - for (std::vector<ValuePair>::iterator T = SS->second.begin(), - TE = SS->second.end(); T != TE; ++T) { - VPPair Q(*S, *T); - if (!PrunedDAG.count(Q.second)) - continue; - DenseMap<VPPair, unsigned>::iterator R = - PairConnectionTypes.find(VPPair(Q.second, Q.first)); - assert(R != PairConnectionTypes.end() && - "Cannot find pair connection type"); - Type *Ty1 = Q.second.first->getType(), - *Ty2 = Q.second.second->getType(); - Type *VTy = getVecTypeForPair(Ty1, Ty2); - if ((R->second == PairConnectionDirect && FlipOrder) || - (R->second == PairConnectionSwap && !FlipOrder) || - R->second == PairConnectionSplat) { - int ESContrib = (int) getInstrCost(Instruction::ShuffleVector, - VTy, VTy); - - if (VTy->getVectorNumElements() == 2) { - if (R->second == PairConnectionSplat) - ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost( - TargetTransformInfo::SK_Broadcast, VTy)); - else - ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost( - TargetTransformInfo::SK_Reverse, VTy)); - } - - DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" << - *Q.second.first << " <-> " << *Q.second.second << - "} -> {" << - *S->first << " <-> " << *S->second << "} = " << - ESContrib << "\n"); - EffSize -= ESContrib; - } - } - } - - // Compute the cost of outgoing edges. We assume that edges outgoing - // to shuffles, inserts or extracts can be merged, and so contribute - // no additional cost. - if (!S->first->getType()->isVoidTy()) { - Type *Ty1 = S->first->getType(), - *Ty2 = S->second->getType(); - Type *VTy = getVecTypeForPair(Ty1, Ty2); - - bool NeedsExtraction = false; - for (User *U : S->first->users()) { - if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(U)) { - // Shuffle can be folded if it has no other input - if (isa<UndefValue>(SI->getOperand(1))) - continue; - } - if (isa<ExtractElementInst>(U)) - continue; - if (PrunedDAGInstrs.count(U)) - continue; - NeedsExtraction = true; - break; - } - - if (NeedsExtraction) { - int ESContrib; - if (Ty1->isVectorTy()) { - ESContrib = (int) getInstrCost(Instruction::ShuffleVector, - Ty1, VTy); - ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost( - TargetTransformInfo::SK_ExtractSubvector, VTy, 0, Ty1)); - } else - ESContrib = (int) TTI->getVectorInstrCost( - Instruction::ExtractElement, VTy, 0); - - DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" << - *S->first << "} = " << ESContrib << "\n"); - EffSize -= ESContrib; - } - - NeedsExtraction = false; - for (User *U : S->second->users()) { - if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(U)) { - // Shuffle can be folded if it has no other input - if (isa<UndefValue>(SI->getOperand(1))) - continue; - } - if (isa<ExtractElementInst>(U)) - continue; - if (PrunedDAGInstrs.count(U)) - continue; - NeedsExtraction = true; - break; - } - - if (NeedsExtraction) { - int ESContrib; - if (Ty2->isVectorTy()) { - ESContrib = (int) getInstrCost(Instruction::ShuffleVector, - Ty2, VTy); - ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost( - TargetTransformInfo::SK_ExtractSubvector, VTy, - Ty1->isVectorTy() ? Ty1->getVectorNumElements() : 1, Ty2)); - } else - ESContrib = (int) TTI->getVectorInstrCost( - Instruction::ExtractElement, VTy, 1); - DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" << - *S->second << "} = " << ESContrib << "\n"); - EffSize -= ESContrib; - } - } - - // Compute the cost of incoming edges. - if (!isa<LoadInst>(S->first) && !isa<StoreInst>(S->first)) { - Instruction *S1 = cast<Instruction>(S->first), - *S2 = cast<Instruction>(S->second); - for (unsigned o = 0; o < S1->getNumOperands(); ++o) { - Value *O1 = S1->getOperand(o), *O2 = S2->getOperand(o); - - // Combining constants into vector constants (or small vector - // constants into larger ones are assumed free). - if (isa<Constant>(O1) && isa<Constant>(O2)) - continue; - - if (FlipOrder) - std::swap(O1, O2); - - ValuePair VP = ValuePair(O1, O2); - ValuePair VPR = ValuePair(O2, O1); - - // Internal edges are not handled here. - if (PrunedDAG.count(VP) || PrunedDAG.count(VPR)) - continue; - - Type *Ty1 = O1->getType(), - *Ty2 = O2->getType(); - Type *VTy = getVecTypeForPair(Ty1, Ty2); - - // Combining vector operations of the same type is also assumed - // folded with other operations. - if (Ty1 == Ty2) { - // If both are insert elements, then both can be widened. - InsertElementInst *IEO1 = dyn_cast<InsertElementInst>(O1), - *IEO2 = dyn_cast<InsertElementInst>(O2); - if (IEO1 && IEO2 && isPureIEChain(IEO1) && isPureIEChain(IEO2)) - continue; - // If both are extract elements, and both have the same input - // type, then they can be replaced with a shuffle - ExtractElementInst *EIO1 = dyn_cast<ExtractElementInst>(O1), - *EIO2 = dyn_cast<ExtractElementInst>(O2); - if (EIO1 && EIO2 && - EIO1->getOperand(0)->getType() == - EIO2->getOperand(0)->getType()) - continue; - // If both are a shuffle with equal operand types and only two - // unqiue operands, then they can be replaced with a single - // shuffle - ShuffleVectorInst *SIO1 = dyn_cast<ShuffleVectorInst>(O1), - *SIO2 = dyn_cast<ShuffleVectorInst>(O2); - if (SIO1 && SIO2 && - SIO1->getOperand(0)->getType() == - SIO2->getOperand(0)->getType()) { - SmallSet<Value *, 4> SIOps; - SIOps.insert(SIO1->getOperand(0)); - SIOps.insert(SIO1->getOperand(1)); - SIOps.insert(SIO2->getOperand(0)); - SIOps.insert(SIO2->getOperand(1)); - if (SIOps.size() <= 2) - continue; - } - } - - int ESContrib; - // This pair has already been formed. - if (IncomingPairs.count(VP)) { - continue; - } else if (IncomingPairs.count(VPR)) { - ESContrib = (int) getInstrCost(Instruction::ShuffleVector, - VTy, VTy); - - if (VTy->getVectorNumElements() == 2) - ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost( - TargetTransformInfo::SK_Reverse, VTy)); - } else if (!Ty1->isVectorTy() && !Ty2->isVectorTy()) { - ESContrib = (int) TTI->getVectorInstrCost( - Instruction::InsertElement, VTy, 0); - ESContrib += (int) TTI->getVectorInstrCost( - Instruction::InsertElement, VTy, 1); - } else if (!Ty1->isVectorTy()) { - // O1 needs to be inserted into a vector of size O2, and then - // both need to be shuffled together. - ESContrib = (int) TTI->getVectorInstrCost( - Instruction::InsertElement, Ty2, 0); - ESContrib += (int) getInstrCost(Instruction::ShuffleVector, - VTy, Ty2); - } else if (!Ty2->isVectorTy()) { - // O2 needs to be inserted into a vector of size O1, and then - // both need to be shuffled together. - ESContrib = (int) TTI->getVectorInstrCost( - Instruction::InsertElement, Ty1, 0); - ESContrib += (int) getInstrCost(Instruction::ShuffleVector, - VTy, Ty1); - } else { - Type *TyBig = Ty1, *TySmall = Ty2; - if (Ty2->getVectorNumElements() > Ty1->getVectorNumElements()) - std::swap(TyBig, TySmall); - - ESContrib = (int) getInstrCost(Instruction::ShuffleVector, - VTy, TyBig); - if (TyBig != TySmall) - ESContrib += (int) getInstrCost(Instruction::ShuffleVector, - TyBig, TySmall); - } - - DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" - << *O1 << " <-> " << *O2 << "} = " << - ESContrib << "\n"); - EffSize -= ESContrib; - IncomingPairs.insert(VP); - } - } - } - - if (!HasNontrivialInsts) { - DEBUG(if (DebugPairSelection) dbgs() << - "\tNo non-trivial instructions in DAG;" - " override to zero effective size\n"); - EffSize = 0; - } - } else { - for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(), - E = PrunedDAG.end(); S != E; ++S) - EffSize += (int) getDepthFactor(S->first); - } - - DEBUG(if (DebugPairSelection) - dbgs() << "BBV: found pruned DAG for pair {" - << *IJ.first << " <-> " << *IJ.second << "} of depth " << - MaxDepth << " and size " << PrunedDAG.size() << - " (effective size: " << EffSize << ")\n"); - if (((TTI && !UseChainDepthWithTI) || - MaxDepth >= Config.ReqChainDepth) && - EffSize > 0 && EffSize > BestEffSize) { - BestMaxDepth = MaxDepth; - BestEffSize = EffSize; - BestDAG = PrunedDAG; - } - } - } - - // Given the list of candidate pairs, this function selects those - // that will be fused into vector instructions. - void BBVectorize::choosePairs( - DenseMap<Value *, std::vector<Value *> > &CandidatePairs, - DenseSet<ValuePair> &CandidatePairsSet, - DenseMap<ValuePair, int> &CandidatePairCostSavings, - std::vector<Value *> &PairableInsts, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps, - DenseSet<ValuePair> &PairableInstUsers, - DenseMap<Value *, Value *>& ChosenPairs) { - bool UseCycleCheck = - CandidatePairsSet.size() <= Config.MaxCandPairsForCycleCheck; - - DenseMap<Value *, std::vector<Value *> > CandidatePairs2; - for (DenseSet<ValuePair>::iterator I = CandidatePairsSet.begin(), - E = CandidatePairsSet.end(); I != E; ++I) { - std::vector<Value *> &JJ = CandidatePairs2[I->second]; - if (JJ.empty()) JJ.reserve(32); - JJ.push_back(I->first); - } - - DenseMap<ValuePair, std::vector<ValuePair> > PairableInstUserMap; - DenseSet<VPPair> PairableInstUserPairSet; - for (std::vector<Value *>::iterator I = PairableInsts.begin(), - E = PairableInsts.end(); I != E; ++I) { - // The number of possible pairings for this variable: - size_t NumChoices = CandidatePairs.lookup(*I).size(); - if (!NumChoices) continue; - - std::vector<Value *> &JJ = CandidatePairs[*I]; - - // The best pair to choose and its dag: - size_t BestMaxDepth = 0; - int BestEffSize = 0; - DenseSet<ValuePair> BestDAG; - findBestDAGFor(CandidatePairs, CandidatePairsSet, - CandidatePairCostSavings, - PairableInsts, FixedOrderPairs, PairConnectionTypes, - ConnectedPairs, ConnectedPairDeps, - PairableInstUsers, PairableInstUserMap, - PairableInstUserPairSet, ChosenPairs, - BestDAG, BestMaxDepth, BestEffSize, *I, JJ, - UseCycleCheck); - - if (BestDAG.empty()) - continue; - - // A dag has been chosen (or not) at this point. If no dag was - // chosen, then this instruction, I, cannot be paired (and is no longer - // considered). - - DEBUG(dbgs() << "BBV: selected pairs in the best DAG for: " - << *cast<Instruction>(*I) << "\n"); - - for (DenseSet<ValuePair>::iterator S = BestDAG.begin(), - SE2 = BestDAG.end(); S != SE2; ++S) { - // Insert the members of this dag into the list of chosen pairs. - ChosenPairs.insert(ValuePair(S->first, S->second)); - DEBUG(dbgs() << "BBV: selected pair: " << *S->first << " <-> " << - *S->second << "\n"); - - // Remove all candidate pairs that have values in the chosen dag. - std::vector<Value *> &KK = CandidatePairs[S->first]; - for (std::vector<Value *>::iterator K = KK.begin(), KE = KK.end(); - K != KE; ++K) { - if (*K == S->second) - continue; - - CandidatePairsSet.erase(ValuePair(S->first, *K)); - } - - std::vector<Value *> &LL = CandidatePairs2[S->second]; - for (std::vector<Value *>::iterator L = LL.begin(), LE = LL.end(); - L != LE; ++L) { - if (*L == S->first) - continue; - - CandidatePairsSet.erase(ValuePair(*L, S->second)); - } - - std::vector<Value *> &MM = CandidatePairs[S->second]; - for (std::vector<Value *>::iterator M = MM.begin(), ME = MM.end(); - M != ME; ++M) { - assert(*M != S->first && "Flipped pair in candidate list?"); - CandidatePairsSet.erase(ValuePair(S->second, *M)); - } - - std::vector<Value *> &NN = CandidatePairs2[S->first]; - for (std::vector<Value *>::iterator N = NN.begin(), NE = NN.end(); - N != NE; ++N) { - assert(*N != S->second && "Flipped pair in candidate list?"); - CandidatePairsSet.erase(ValuePair(*N, S->first)); - } - } - } - - DEBUG(dbgs() << "BBV: selected " << ChosenPairs.size() << " pairs.\n"); - } - - std::string getReplacementName(Instruction *I, bool IsInput, unsigned o, - unsigned n = 0) { - if (!I->hasName()) - return ""; - - return (I->getName() + (IsInput ? ".v.i" : ".v.r") + utostr(o) + - (n > 0 ? "." + utostr(n) : "")).str(); - } - - // Returns the value that is to be used as the pointer input to the vector - // instruction that fuses I with J. - Value *BBVectorize::getReplacementPointerInput(LLVMContext& Context, - Instruction *I, Instruction *J, unsigned o) { - Value *IPtr, *JPtr; - unsigned IAlignment, JAlignment, IAddressSpace, JAddressSpace; - int64_t OffsetInElmts; - - // Note: the analysis might fail here, that is why the pair order has - // been precomputed (OffsetInElmts must be unused here). - (void) getPairPtrInfo(I, J, IPtr, JPtr, IAlignment, JAlignment, - IAddressSpace, JAddressSpace, - OffsetInElmts, false); - - // The pointer value is taken to be the one with the lowest offset. - Value *VPtr = IPtr; - - Type *ArgTypeI = IPtr->getType()->getPointerElementType(); - Type *ArgTypeJ = JPtr->getType()->getPointerElementType(); - Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ); - Type *VArgPtrType - = PointerType::get(VArgType, - IPtr->getType()->getPointerAddressSpace()); - return new BitCastInst(VPtr, VArgPtrType, getReplacementName(I, true, o), - /* insert before */ I); - } - - void BBVectorize::fillNewShuffleMask(LLVMContext& Context, Instruction *J, - unsigned MaskOffset, unsigned NumInElem, - unsigned NumInElem1, unsigned IdxOffset, - std::vector<Constant*> &Mask) { - unsigned NumElem1 = J->getType()->getVectorNumElements(); - for (unsigned v = 0; v < NumElem1; ++v) { - int m = cast<ShuffleVectorInst>(J)->getMaskValue(v); - if (m < 0) { - Mask[v+MaskOffset] = UndefValue::get(Type::getInt32Ty(Context)); - } else { - unsigned mm = m + (int) IdxOffset; - if (m >= (int) NumInElem1) - mm += (int) NumInElem; - - Mask[v+MaskOffset] = - ConstantInt::get(Type::getInt32Ty(Context), mm); - } - } - } - - // Returns the value that is to be used as the vector-shuffle mask to the - // vector instruction that fuses I with J. - Value *BBVectorize::getReplacementShuffleMask(LLVMContext& Context, - Instruction *I, Instruction *J) { - // This is the shuffle mask. We need to append the second - // mask to the first, and the numbers need to be adjusted. - - Type *ArgTypeI = I->getType(); - Type *ArgTypeJ = J->getType(); - Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ); - - unsigned NumElemI = ArgTypeI->getVectorNumElements(); - - // Get the total number of elements in the fused vector type. - // By definition, this must equal the number of elements in - // the final mask. - unsigned NumElem = VArgType->getVectorNumElements(); - std::vector<Constant*> Mask(NumElem); - - Type *OpTypeI = I->getOperand(0)->getType(); - unsigned NumInElemI = OpTypeI->getVectorNumElements(); - Type *OpTypeJ = J->getOperand(0)->getType(); - unsigned NumInElemJ = OpTypeJ->getVectorNumElements(); - - // The fused vector will be: - // ----------------------------------------------------- - // | NumInElemI | NumInElemJ | NumInElemI | NumInElemJ | - // ----------------------------------------------------- - // from which we'll extract NumElem total elements (where the first NumElemI - // of them come from the mask in I and the remainder come from the mask - // in J. - - // For the mask from the first pair... - fillNewShuffleMask(Context, I, 0, NumInElemJ, NumInElemI, - 0, Mask); - - // For the mask from the second pair... - fillNewShuffleMask(Context, J, NumElemI, NumInElemI, NumInElemJ, - NumInElemI, Mask); - - return ConstantVector::get(Mask); - } - - bool BBVectorize::expandIEChain(LLVMContext& Context, Instruction *I, - Instruction *J, unsigned o, Value *&LOp, - unsigned numElemL, - Type *ArgTypeL, Type *ArgTypeH, - bool IBeforeJ, unsigned IdxOff) { - bool ExpandedIEChain = false; - if (InsertElementInst *LIE = dyn_cast<InsertElementInst>(LOp)) { - // If we have a pure insertelement chain, then this can be rewritten - // into a chain that directly builds the larger type. - if (isPureIEChain(LIE)) { - SmallVector<Value *, 8> VectElemts(numElemL, - UndefValue::get(ArgTypeL->getScalarType())); - InsertElementInst *LIENext = LIE; - do { - unsigned Idx = - cast<ConstantInt>(LIENext->getOperand(2))->getSExtValue(); - VectElemts[Idx] = LIENext->getOperand(1); - } while ((LIENext = - dyn_cast<InsertElementInst>(LIENext->getOperand(0)))); - - LIENext = nullptr; - Value *LIEPrev = UndefValue::get(ArgTypeH); - for (unsigned i = 0; i < numElemL; ++i) { - if (isa<UndefValue>(VectElemts[i])) continue; - LIENext = InsertElementInst::Create(LIEPrev, VectElemts[i], - ConstantInt::get(Type::getInt32Ty(Context), - i + IdxOff), - getReplacementName(IBeforeJ ? I : J, - true, o, i+1)); - LIENext->insertBefore(IBeforeJ ? J : I); - LIEPrev = LIENext; - } - - LOp = LIENext ? (Value*) LIENext : UndefValue::get(ArgTypeH); - ExpandedIEChain = true; - } - } - - return ExpandedIEChain; - } - - static unsigned getNumScalarElements(Type *Ty) { - if (VectorType *VecTy = dyn_cast<VectorType>(Ty)) - return VecTy->getNumElements(); - return 1; - } - - // Returns the value to be used as the specified operand of the vector - // instruction that fuses I with J. - Value *BBVectorize::getReplacementInput(LLVMContext& Context, Instruction *I, - Instruction *J, unsigned o, bool IBeforeJ) { - Value *CV0 = ConstantInt::get(Type::getInt32Ty(Context), 0); - Value *CV1 = ConstantInt::get(Type::getInt32Ty(Context), 1); - - // Compute the fused vector type for this operand - Type *ArgTypeI = I->getOperand(o)->getType(); - Type *ArgTypeJ = J->getOperand(o)->getType(); - VectorType *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ); - - Instruction *L = I, *H = J; - Type *ArgTypeL = ArgTypeI, *ArgTypeH = ArgTypeJ; - - unsigned numElemL = getNumScalarElements(ArgTypeL); - unsigned numElemH = getNumScalarElements(ArgTypeH); - - Value *LOp = L->getOperand(o); - Value *HOp = H->getOperand(o); - unsigned numElem = VArgType->getNumElements(); - - // First, we check if we can reuse the "original" vector outputs (if these - // exist). We might need a shuffle. - ExtractElementInst *LEE = dyn_cast<ExtractElementInst>(LOp); - ExtractElementInst *HEE = dyn_cast<ExtractElementInst>(HOp); - ShuffleVectorInst *LSV = dyn_cast<ShuffleVectorInst>(LOp); - ShuffleVectorInst *HSV = dyn_cast<ShuffleVectorInst>(HOp); - - // FIXME: If we're fusing shuffle instructions, then we can't apply this - // optimization. The input vectors to the shuffle might be a different - // length from the shuffle outputs. Unfortunately, the replacement - // shuffle mask has already been formed, and the mask entries are sensitive - // to the sizes of the inputs. - bool IsSizeChangeShuffle = - isa<ShuffleVectorInst>(L) && - (LOp->getType() != L->getType() || HOp->getType() != H->getType()); - - if ((LEE || LSV) && (HEE || HSV) && !IsSizeChangeShuffle) { - // We can have at most two unique vector inputs. - bool CanUseInputs = true; - Value *I1, *I2 = nullptr; - if (LEE) { - I1 = LEE->getOperand(0); - } else { - I1 = LSV->getOperand(0); - I2 = LSV->getOperand(1); - if (I2 == I1 || isa<UndefValue>(I2)) - I2 = nullptr; - } - - if (HEE) { - Value *I3 = HEE->getOperand(0); - if (!I2 && I3 != I1) - I2 = I3; - else if (I3 != I1 && I3 != I2) - CanUseInputs = false; - } else { - Value *I3 = HSV->getOperand(0); - if (!I2 && I3 != I1) - I2 = I3; - else if (I3 != I1 && I3 != I2) - CanUseInputs = false; - - if (CanUseInputs) { - Value *I4 = HSV->getOperand(1); - if (!isa<UndefValue>(I4)) { - if (!I2 && I4 != I1) - I2 = I4; - else if (I4 != I1 && I4 != I2) - CanUseInputs = false; - } - } - } - - if (CanUseInputs) { - unsigned LOpElem = - cast<Instruction>(LOp)->getOperand(0)->getType() - ->getVectorNumElements(); - - unsigned HOpElem = - cast<Instruction>(HOp)->getOperand(0)->getType() - ->getVectorNumElements(); - - // We have one or two input vectors. We need to map each index of the - // operands to the index of the original vector. - SmallVector<std::pair<int, int>, 8> II(numElem); - for (unsigned i = 0; i < numElemL; ++i) { - int Idx, INum; - if (LEE) { - Idx = - cast<ConstantInt>(LEE->getOperand(1))->getSExtValue(); - INum = LEE->getOperand(0) == I1 ? 0 : 1; - } else { - Idx = LSV->getMaskValue(i); - if (Idx < (int) LOpElem) { - INum = LSV->getOperand(0) == I1 ? 0 : 1; - } else { - Idx -= LOpElem; - INum = LSV->getOperand(1) == I1 ? 0 : 1; - } - } - - II[i] = std::pair<int, int>(Idx, INum); - } - for (unsigned i = 0; i < numElemH; ++i) { - int Idx, INum; - if (HEE) { - Idx = - cast<ConstantInt>(HEE->getOperand(1))->getSExtValue(); - INum = HEE->getOperand(0) == I1 ? 0 : 1; - } else { - Idx = HSV->getMaskValue(i); - if (Idx < (int) HOpElem) { - INum = HSV->getOperand(0) == I1 ? 0 : 1; - } else { - Idx -= HOpElem; - INum = HSV->getOperand(1) == I1 ? 0 : 1; - } - } - - II[i + numElemL] = std::pair<int, int>(Idx, INum); - } - - // We now have an array which tells us from which index of which - // input vector each element of the operand comes. - VectorType *I1T = cast<VectorType>(I1->getType()); - unsigned I1Elem = I1T->getNumElements(); - - if (!I2) { - // In this case there is only one underlying vector input. Check for - // the trivial case where we can use the input directly. - if (I1Elem == numElem) { - bool ElemInOrder = true; - for (unsigned i = 0; i < numElem; ++i) { - if (II[i].first != (int) i && II[i].first != -1) { - ElemInOrder = false; - break; - } - } - - if (ElemInOrder) - return I1; - } - - // A shuffle is needed. - std::vector<Constant *> Mask(numElem); - for (unsigned i = 0; i < numElem; ++i) { - int Idx = II[i].first; - if (Idx == -1) - Mask[i] = UndefValue::get(Type::getInt32Ty(Context)); - else - Mask[i] = ConstantInt::get(Type::getInt32Ty(Context), Idx); - } - - Instruction *S = - new ShuffleVectorInst(I1, UndefValue::get(I1T), - ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, - true, o)); - S->insertBefore(IBeforeJ ? J : I); - return S; - } - - VectorType *I2T = cast<VectorType>(I2->getType()); - unsigned I2Elem = I2T->getNumElements(); - - // This input comes from two distinct vectors. The first step is to - // make sure that both vectors are the same length. If not, the - // smaller one will need to grow before they can be shuffled together. - if (I1Elem < I2Elem) { - std::vector<Constant *> Mask(I2Elem); - unsigned v = 0; - for (; v < I1Elem; ++v) - Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v); - for (; v < I2Elem; ++v) - Mask[v] = UndefValue::get(Type::getInt32Ty(Context)); - - Instruction *NewI1 = - new ShuffleVectorInst(I1, UndefValue::get(I1T), - ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - NewI1->insertBefore(IBeforeJ ? J : I); - I1 = NewI1; - I1Elem = I2Elem; - } else if (I1Elem > I2Elem) { - std::vector<Constant *> Mask(I1Elem); - unsigned v = 0; - for (; v < I2Elem; ++v) - Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v); - for (; v < I1Elem; ++v) - Mask[v] = UndefValue::get(Type::getInt32Ty(Context)); - - Instruction *NewI2 = - new ShuffleVectorInst(I2, UndefValue::get(I2T), - ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - NewI2->insertBefore(IBeforeJ ? J : I); - I2 = NewI2; - } - - // Now that both I1 and I2 are the same length we can shuffle them - // together (and use the result). - std::vector<Constant *> Mask(numElem); - for (unsigned v = 0; v < numElem; ++v) { - if (II[v].first == -1) { - Mask[v] = UndefValue::get(Type::getInt32Ty(Context)); - } else { - int Idx = II[v].first + II[v].second * I1Elem; - Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), Idx); - } - } - - Instruction *NewOp = - new ShuffleVectorInst(I1, I2, ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, true, o)); - NewOp->insertBefore(IBeforeJ ? J : I); - return NewOp; - } - } - - Type *ArgType = ArgTypeL; - if (numElemL < numElemH) { - if (numElemL == 1 && expandIEChain(Context, I, J, o, HOp, numElemH, - ArgTypeL, VArgType, IBeforeJ, 1)) { - // This is another short-circuit case: we're combining a scalar into - // a vector that is formed by an IE chain. We've just expanded the IE - // chain, now insert the scalar and we're done. - - Instruction *S = InsertElementInst::Create(HOp, LOp, CV0, - getReplacementName(IBeforeJ ? I : J, true, o)); - S->insertBefore(IBeforeJ ? J : I); - return S; - } else if (!expandIEChain(Context, I, J, o, LOp, numElemL, ArgTypeL, - ArgTypeH, IBeforeJ)) { - // The two vector inputs to the shuffle must be the same length, - // so extend the smaller vector to be the same length as the larger one. - Instruction *NLOp; - if (numElemL > 1) { - - std::vector<Constant *> Mask(numElemH); - unsigned v = 0; - for (; v < numElemL; ++v) - Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v); - for (; v < numElemH; ++v) - Mask[v] = UndefValue::get(Type::getInt32Ty(Context)); - - NLOp = new ShuffleVectorInst(LOp, UndefValue::get(ArgTypeL), - ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - } else { - NLOp = InsertElementInst::Create(UndefValue::get(ArgTypeH), LOp, CV0, - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - } - - NLOp->insertBefore(IBeforeJ ? J : I); - LOp = NLOp; - } - - ArgType = ArgTypeH; - } else if (numElemL > numElemH) { - if (numElemH == 1 && expandIEChain(Context, I, J, o, LOp, numElemL, - ArgTypeH, VArgType, IBeforeJ)) { - Instruction *S = - InsertElementInst::Create(LOp, HOp, - ConstantInt::get(Type::getInt32Ty(Context), - numElemL), - getReplacementName(IBeforeJ ? I : J, - true, o)); - S->insertBefore(IBeforeJ ? J : I); - return S; - } else if (!expandIEChain(Context, I, J, o, HOp, numElemH, ArgTypeH, - ArgTypeL, IBeforeJ)) { - Instruction *NHOp; - if (numElemH > 1) { - std::vector<Constant *> Mask(numElemL); - unsigned v = 0; - for (; v < numElemH; ++v) - Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v); - for (; v < numElemL; ++v) - Mask[v] = UndefValue::get(Type::getInt32Ty(Context)); - - NHOp = new ShuffleVectorInst(HOp, UndefValue::get(ArgTypeH), - ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - } else { - NHOp = InsertElementInst::Create(UndefValue::get(ArgTypeL), HOp, CV0, - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - } - - NHOp->insertBefore(IBeforeJ ? J : I); - HOp = NHOp; - } - } - - if (ArgType->isVectorTy()) { - unsigned numElem = VArgType->getVectorNumElements(); - std::vector<Constant*> Mask(numElem); - for (unsigned v = 0; v < numElem; ++v) { - unsigned Idx = v; - // If the low vector was expanded, we need to skip the extra - // undefined entries. - if (v >= numElemL && numElemH > numElemL) - Idx += (numElemH - numElemL); - Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), Idx); - } - - Instruction *BV = new ShuffleVectorInst(LOp, HOp, - ConstantVector::get(Mask), - getReplacementName(IBeforeJ ? I : J, true, o)); - BV->insertBefore(IBeforeJ ? J : I); - return BV; - } - - Instruction *BV1 = InsertElementInst::Create( - UndefValue::get(VArgType), LOp, CV0, - getReplacementName(IBeforeJ ? I : J, - true, o, 1)); - BV1->insertBefore(IBeforeJ ? J : I); - Instruction *BV2 = InsertElementInst::Create(BV1, HOp, CV1, - getReplacementName(IBeforeJ ? I : J, - true, o, 2)); - BV2->insertBefore(IBeforeJ ? J : I); - return BV2; - } - - // This function creates an array of values that will be used as the inputs - // to the vector instruction that fuses I with J. - void BBVectorize::getReplacementInputsForPair(LLVMContext& Context, - Instruction *I, Instruction *J, - SmallVectorImpl<Value *> &ReplacedOperands, - bool IBeforeJ) { - unsigned NumOperands = I->getNumOperands(); - - for (unsigned p = 0, o = NumOperands-1; p < NumOperands; ++p, --o) { - // Iterate backward so that we look at the store pointer - // first and know whether or not we need to flip the inputs. - - if (isa<LoadInst>(I) || (o == 1 && isa<StoreInst>(I))) { - // This is the pointer for a load/store instruction. - ReplacedOperands[o] = getReplacementPointerInput(Context, I, J, o); - continue; - } else if (isa<CallInst>(I)) { - Function *F = cast<CallInst>(I)->getCalledFunction(); - Intrinsic::ID IID = F->getIntrinsicID(); - if (o == NumOperands-1) { - BasicBlock &BB = *I->getParent(); - - Module *M = BB.getParent()->getParent(); - Type *ArgTypeI = I->getType(); - Type *ArgTypeJ = J->getType(); - Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ); - - ReplacedOperands[o] = Intrinsic::getDeclaration(M, IID, VArgType); - continue; - } else if ((IID == Intrinsic::powi || IID == Intrinsic::ctlz || - IID == Intrinsic::cttz) && o == 1) { - // The second argument of powi/ctlz/cttz is a single integer/constant - // and we've already checked that both arguments are equal. - // As a result, we just keep I's second argument. - ReplacedOperands[o] = I->getOperand(o); - continue; - } - } else if (isa<ShuffleVectorInst>(I) && o == NumOperands-1) { - ReplacedOperands[o] = getReplacementShuffleMask(Context, I, J); - continue; - } - - ReplacedOperands[o] = getReplacementInput(Context, I, J, o, IBeforeJ); - } - } - - // This function creates two values that represent the outputs of the - // original I and J instructions. These are generally vector shuffles - // or extracts. In many cases, these will end up being unused and, thus, - // eliminated by later passes. - void BBVectorize::replaceOutputsOfPair(LLVMContext& Context, Instruction *I, - Instruction *J, Instruction *K, - Instruction *&InsertionPt, - Instruction *&K1, Instruction *&K2) { - if (isa<StoreInst>(I)) - return; - - Type *IType = I->getType(); - Type *JType = J->getType(); - - VectorType *VType = getVecTypeForPair(IType, JType); - unsigned numElem = VType->getNumElements(); - - unsigned numElemI = getNumScalarElements(IType); - unsigned numElemJ = getNumScalarElements(JType); - - if (IType->isVectorTy()) { - std::vector<Constant *> Mask1(numElemI), Mask2(numElemI); - for (unsigned v = 0; v < numElemI; ++v) { - Mask1[v] = ConstantInt::get(Type::getInt32Ty(Context), v); - Mask2[v] = ConstantInt::get(Type::getInt32Ty(Context), numElemJ + v); - } - - K1 = new ShuffleVectorInst(K, UndefValue::get(VType), - ConstantVector::get(Mask1), - getReplacementName(K, false, 1)); - } else { - Value *CV0 = ConstantInt::get(Type::getInt32Ty(Context), 0); - K1 = ExtractElementInst::Create(K, CV0, getReplacementName(K, false, 1)); - } - - if (JType->isVectorTy()) { - std::vector<Constant *> Mask1(numElemJ), Mask2(numElemJ); - for (unsigned v = 0; v < numElemJ; ++v) { - Mask1[v] = ConstantInt::get(Type::getInt32Ty(Context), v); - Mask2[v] = ConstantInt::get(Type::getInt32Ty(Context), numElemI + v); - } - - K2 = new ShuffleVectorInst(K, UndefValue::get(VType), - ConstantVector::get(Mask2), - getReplacementName(K, false, 2)); - } else { - Value *CV1 = ConstantInt::get(Type::getInt32Ty(Context), numElem - 1); - K2 = ExtractElementInst::Create(K, CV1, getReplacementName(K, false, 2)); - } - - K1->insertAfter(K); - K2->insertAfter(K1); - InsertionPt = K2; - } - - // Move all uses of the function I (including pairing-induced uses) after J. - bool BBVectorize::canMoveUsesOfIAfterJ(BasicBlock &BB, - DenseSet<ValuePair> &LoadMoveSetPairs, - Instruction *I, Instruction *J) { - // Skip to the first instruction past I. - BasicBlock::iterator L = std::next(BasicBlock::iterator(I)); - - DenseSet<Value *> Users; - AliasSetTracker WriteSet(*AA); - if (I->mayWriteToMemory()) WriteSet.add(I); - - for (; cast<Instruction>(L) != J; ++L) - (void)trackUsesOfI(Users, WriteSet, I, &*L, true, &LoadMoveSetPairs); - - assert(cast<Instruction>(L) == J && - "Tracking has not proceeded far enough to check for dependencies"); - // If J is now in the use set of I, then trackUsesOfI will return true - // and we have a dependency cycle (and the fusing operation must abort). - return !trackUsesOfI(Users, WriteSet, I, J, true, &LoadMoveSetPairs); - } - - // Move all uses of the function I (including pairing-induced uses) after J. - void BBVectorize::moveUsesOfIAfterJ(BasicBlock &BB, - DenseSet<ValuePair> &LoadMoveSetPairs, - Instruction *&InsertionPt, - Instruction *I, Instruction *J) { - // Skip to the first instruction past I. - BasicBlock::iterator L = std::next(BasicBlock::iterator(I)); - - DenseSet<Value *> Users; - AliasSetTracker WriteSet(*AA); - if (I->mayWriteToMemory()) WriteSet.add(I); - - for (; cast<Instruction>(L) != J;) { - if (trackUsesOfI(Users, WriteSet, I, &*L, true, &LoadMoveSetPairs)) { - // Move this instruction - Instruction *InstToMove = &*L++; - - DEBUG(dbgs() << "BBV: moving: " << *InstToMove << - " to after " << *InsertionPt << "\n"); - InstToMove->removeFromParent(); - InstToMove->insertAfter(InsertionPt); - InsertionPt = InstToMove; - } else { - ++L; - } - } - } - - // Collect all load instruction that are in the move set of a given first - // pair member. These loads depend on the first instruction, I, and so need - // to be moved after J (the second instruction) when the pair is fused. - void BBVectorize::collectPairLoadMoveSet(BasicBlock &BB, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<Value *, std::vector<Value *> > &LoadMoveSet, - DenseSet<ValuePair> &LoadMoveSetPairs, - Instruction *I) { - // Skip to the first instruction past I. - BasicBlock::iterator L = std::next(BasicBlock::iterator(I)); - - DenseSet<Value *> Users; - AliasSetTracker WriteSet(*AA); - if (I->mayWriteToMemory()) WriteSet.add(I); - - // Note: We cannot end the loop when we reach J because J could be moved - // farther down the use chain by another instruction pairing. Also, J - // could be before I if this is an inverted input. - for (BasicBlock::iterator E = BB.end(); L != E; ++L) { - if (trackUsesOfI(Users, WriteSet, I, &*L)) { - if (L->mayReadFromMemory()) { - LoadMoveSet[&*L].push_back(I); - LoadMoveSetPairs.insert(ValuePair(&*L, I)); - } - } - } - } - - // In cases where both load/stores and the computation of their pointers - // are chosen for vectorization, we can end up in a situation where the - // aliasing analysis starts returning different query results as the - // process of fusing instruction pairs continues. Because the algorithm - // relies on finding the same use dags here as were found earlier, we'll - // need to precompute the necessary aliasing information here and then - // manually update it during the fusion process. - void BBVectorize::collectLoadMoveSet(BasicBlock &BB, - std::vector<Value *> &PairableInsts, - DenseMap<Value *, Value *> &ChosenPairs, - DenseMap<Value *, std::vector<Value *> > &LoadMoveSet, - DenseSet<ValuePair> &LoadMoveSetPairs) { - for (std::vector<Value *>::iterator PI = PairableInsts.begin(), - PIE = PairableInsts.end(); PI != PIE; ++PI) { - DenseMap<Value *, Value *>::iterator P = ChosenPairs.find(*PI); - if (P == ChosenPairs.end()) continue; - - Instruction *I = cast<Instruction>(P->first); - collectPairLoadMoveSet(BB, ChosenPairs, LoadMoveSet, - LoadMoveSetPairs, I); - } - } - - // This function fuses the chosen instruction pairs into vector instructions, - // taking care preserve any needed scalar outputs and, then, it reorders the - // remaining instructions as needed (users of the first member of the pair - // need to be moved to after the location of the second member of the pair - // because the vector instruction is inserted in the location of the pair's - // second member). - void BBVectorize::fuseChosenPairs(BasicBlock &BB, - std::vector<Value *> &PairableInsts, - DenseMap<Value *, Value *> &ChosenPairs, - DenseSet<ValuePair> &FixedOrderPairs, - DenseMap<VPPair, unsigned> &PairConnectionTypes, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs, - DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps) { - LLVMContext& Context = BB.getContext(); - - // During the vectorization process, the order of the pairs to be fused - // could be flipped. So we'll add each pair, flipped, into the ChosenPairs - // list. After a pair is fused, the flipped pair is removed from the list. - DenseSet<ValuePair> FlippedPairs; - for (DenseMap<Value *, Value *>::iterator P = ChosenPairs.begin(), - E = ChosenPairs.end(); P != E; ++P) - FlippedPairs.insert(ValuePair(P->second, P->first)); - for (DenseSet<ValuePair>::iterator P = FlippedPairs.begin(), - E = FlippedPairs.end(); P != E; ++P) - ChosenPairs.insert(*P); - - DenseMap<Value *, std::vector<Value *> > LoadMoveSet; - DenseSet<ValuePair> LoadMoveSetPairs; - collectLoadMoveSet(BB, PairableInsts, ChosenPairs, - LoadMoveSet, LoadMoveSetPairs); - - DEBUG(dbgs() << "BBV: initial: \n" << BB << "\n"); - - for (BasicBlock::iterator PI = BB.getFirstInsertionPt(); PI != BB.end();) { - DenseMap<Value *, Value *>::iterator P = ChosenPairs.find(&*PI); - if (P == ChosenPairs.end()) { - ++PI; - continue; - } - - if (getDepthFactor(P->first) == 0) { - // These instructions are not really fused, but are tracked as though - // they are. Any case in which it would be interesting to fuse them - // will be taken care of by InstCombine. - --NumFusedOps; - ++PI; - continue; - } - - Instruction *I = cast<Instruction>(P->first), - *J = cast<Instruction>(P->second); - - DEBUG(dbgs() << "BBV: fusing: " << *I << - " <-> " << *J << "\n"); - - // Remove the pair and flipped pair from the list. - DenseMap<Value *, Value *>::iterator FP = ChosenPairs.find(P->second); - assert(FP != ChosenPairs.end() && "Flipped pair not found in list"); - ChosenPairs.erase(FP); - ChosenPairs.erase(P); - - if (!canMoveUsesOfIAfterJ(BB, LoadMoveSetPairs, I, J)) { - DEBUG(dbgs() << "BBV: fusion of: " << *I << - " <-> " << *J << - " aborted because of non-trivial dependency cycle\n"); - --NumFusedOps; - ++PI; - continue; - } - - // If the pair must have the other order, then flip it. - bool FlipPairOrder = FixedOrderPairs.count(ValuePair(J, I)); - if (!FlipPairOrder && !FixedOrderPairs.count(ValuePair(I, J))) { - // This pair does not have a fixed order, and so we might want to - // flip it if that will yield fewer shuffles. We count the number - // of dependencies connected via swaps, and those directly connected, - // and flip the order if the number of swaps is greater. - bool OrigOrder = true; - DenseMap<ValuePair, std::vector<ValuePair> >::iterator IJ = - ConnectedPairDeps.find(ValuePair(I, J)); - if (IJ == ConnectedPairDeps.end()) { - IJ = ConnectedPairDeps.find(ValuePair(J, I)); - OrigOrder = false; - } - - if (IJ != ConnectedPairDeps.end()) { - unsigned NumDepsDirect = 0, NumDepsSwap = 0; - for (std::vector<ValuePair>::iterator T = IJ->second.begin(), - TE = IJ->second.end(); T != TE; ++T) { - VPPair Q(IJ->first, *T); - DenseMap<VPPair, unsigned>::iterator R = - PairConnectionTypes.find(VPPair(Q.second, Q.first)); - assert(R != PairConnectionTypes.end() && - "Cannot find pair connection type"); - if (R->second == PairConnectionDirect) - ++NumDepsDirect; - else if (R->second == PairConnectionSwap) - ++NumDepsSwap; - } - - if (!OrigOrder) - std::swap(NumDepsDirect, NumDepsSwap); - - if (NumDepsSwap > NumDepsDirect) { - FlipPairOrder = true; - DEBUG(dbgs() << "BBV: reordering pair: " << *I << - " <-> " << *J << "\n"); - } - } - } - - Instruction *L = I, *H = J; - if (FlipPairOrder) - std::swap(H, L); - - // If the pair being fused uses the opposite order from that in the pair - // connection map, then we need to flip the types. - DenseMap<ValuePair, std::vector<ValuePair> >::iterator HL = - ConnectedPairs.find(ValuePair(H, L)); - if (HL != ConnectedPairs.end()) - for (std::vector<ValuePair>::iterator T = HL->second.begin(), - TE = HL->second.end(); T != TE; ++T) { - VPPair Q(HL->first, *T); - DenseMap<VPPair, unsigned>::iterator R = PairConnectionTypes.find(Q); - assert(R != PairConnectionTypes.end() && - "Cannot find pair connection type"); - if (R->second == PairConnectionDirect) - R->second = PairConnectionSwap; - else if (R->second == PairConnectionSwap) - R->second = PairConnectionDirect; - } - - bool LBeforeH = !FlipPairOrder; - unsigned NumOperands = I->getNumOperands(); - SmallVector<Value *, 3> ReplacedOperands(NumOperands); - getReplacementInputsForPair(Context, L, H, ReplacedOperands, - LBeforeH); - - // Make a copy of the original operation, change its type to the vector - // type and replace its operands with the vector operands. - Instruction *K = L->clone(); - if (L->hasName()) - K->takeName(L); - else if (H->hasName()) - K->takeName(H); - - if (auto CS = CallSite(K)) { - SmallVector<Type *, 3> Tys; - FunctionType *Old = CS.getFunctionType(); - unsigned NumOld = Old->getNumParams(); - assert(NumOld <= ReplacedOperands.size()); - for (unsigned i = 0; i != NumOld; ++i) - Tys.push_back(ReplacedOperands[i]->getType()); - CS.mutateFunctionType( - FunctionType::get(getVecTypeForPair(L->getType(), H->getType()), - Tys, Old->isVarArg())); - } else if (!isa<StoreInst>(K)) - K->mutateType(getVecTypeForPair(L->getType(), H->getType())); - - unsigned KnownIDs[] = {LLVMContext::MD_tbaa, LLVMContext::MD_alias_scope, - LLVMContext::MD_noalias, LLVMContext::MD_fpmath, - LLVMContext::MD_invariant_group}; - combineMetadata(K, H, KnownIDs); - K->andIRFlags(H); - - for (unsigned o = 0; o < NumOperands; ++o) - K->setOperand(o, ReplacedOperands[o]); - - K->insertAfter(J); - - // Instruction insertion point: - Instruction *InsertionPt = K; - Instruction *K1 = nullptr, *K2 = nullptr; - replaceOutputsOfPair(Context, L, H, K, InsertionPt, K1, K2); - - // The use dag of the first original instruction must be moved to after - // the location of the second instruction. The entire use dag of the - // first instruction is disjoint from the input dag of the second - // (by definition), and so commutes with it. - - moveUsesOfIAfterJ(BB, LoadMoveSetPairs, InsertionPt, I, J); - - if (!isa<StoreInst>(I)) { - L->replaceAllUsesWith(K1); - H->replaceAllUsesWith(K2); - } - - // Instructions that may read from memory may be in the load move set. - // Once an instruction is fused, we no longer need its move set, and so - // the values of the map never need to be updated. However, when a load - // is fused, we need to merge the entries from both instructions in the - // pair in case those instructions were in the move set of some other - // yet-to-be-fused pair. The loads in question are the keys of the map. - if (I->mayReadFromMemory()) { - std::vector<ValuePair> NewSetMembers; - DenseMap<Value *, std::vector<Value *> >::iterator II = - LoadMoveSet.find(I); - if (II != LoadMoveSet.end()) - for (std::vector<Value *>::iterator N = II->second.begin(), - NE = II->second.end(); N != NE; ++N) - NewSetMembers.push_back(ValuePair(K, *N)); - DenseMap<Value *, std::vector<Value *> >::iterator JJ = - LoadMoveSet.find(J); - if (JJ != LoadMoveSet.end()) - for (std::vector<Value *>::iterator N = JJ->second.begin(), - NE = JJ->second.end(); N != NE; ++N) - NewSetMembers.push_back(ValuePair(K, *N)); - for (std::vector<ValuePair>::iterator A = NewSetMembers.begin(), - AE = NewSetMembers.end(); A != AE; ++A) { - LoadMoveSet[A->first].push_back(A->second); - LoadMoveSetPairs.insert(*A); - } - } - - // Before removing I, set the iterator to the next instruction. - PI = std::next(BasicBlock::iterator(I)); - if (cast<Instruction>(PI) == J) - ++PI; - - SE->forgetValue(I); - SE->forgetValue(J); - I->eraseFromParent(); - J->eraseFromParent(); - - DEBUG(if (PrintAfterEveryPair) dbgs() << "BBV: block is now: \n" << - BB << "\n"); - } - - DEBUG(dbgs() << "BBV: final: \n" << BB << "\n"); - } -} - -char BBVectorize::ID = 0; -static const char bb_vectorize_name[] = "Basic-Block Vectorization"; -INITIALIZE_PASS_BEGIN(BBVectorize, BBV_NAME, bb_vectorize_name, false, false) -INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) -INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass) -INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) -INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass) -INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) -INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass) -INITIALIZE_PASS_DEPENDENCY(GlobalsAAWrapperPass) -INITIALIZE_PASS_DEPENDENCY(SCEVAAWrapperPass) -INITIALIZE_PASS_END(BBVectorize, BBV_NAME, bb_vectorize_name, false, false) - -BasicBlockPass *llvm::createBBVectorizePass(const VectorizeConfig &C) { - return new BBVectorize(C); -} - -bool -llvm::vectorizeBasicBlock(Pass *P, BasicBlock &BB, const VectorizeConfig &C) { - BBVectorize BBVectorizer(P, *BB.getParent(), C); - return BBVectorizer.vectorizeBB(BB); -} - -//===----------------------------------------------------------------------===// -VectorizeConfig::VectorizeConfig() { - VectorBits = ::VectorBits; - VectorizeBools = !::NoBools; - VectorizeInts = !::NoInts; - VectorizeFloats = !::NoFloats; - VectorizePointers = !::NoPointers; - VectorizeCasts = !::NoCasts; - VectorizeMath = !::NoMath; - VectorizeBitManipulations = !::NoBitManipulation; - VectorizeFMA = !::NoFMA; - VectorizeSelect = !::NoSelect; - VectorizeCmp = !::NoCmp; - VectorizeGEP = !::NoGEP; - VectorizeMemOps = !::NoMemOps; - AlignedOnly = ::AlignedOnly; - ReqChainDepth= ::ReqChainDepth; - SearchLimit = ::SearchLimit; - MaxCandPairsForCycleCheck = ::MaxCandPairsForCycleCheck; - SplatBreaksChain = ::SplatBreaksChain; - MaxInsts = ::MaxInsts; - MaxPairs = ::MaxPairs; - MaxIter = ::MaxIter; - Pow2LenOnly = ::Pow2LenOnly; - NoMemOpBoost = ::NoMemOpBoost; - FastDep = ::FastDep; -} |