diff options
Diffstat (limited to 'lib/Transforms/Scalar/LoopIdiomRecognize.cpp')
-rw-r--r-- | lib/Transforms/Scalar/LoopIdiomRecognize.cpp | 133 |
1 files changed, 66 insertions, 67 deletions
diff --git a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp index 952b76b822cf..a12f5a7a0334 100644 --- a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp +++ b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp @@ -41,7 +41,6 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "loop-idiom" #include "llvm/Transforms/Scalar.h" #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/AliasAnalysis.h" @@ -51,6 +50,7 @@ #include "llvm/Analysis/TargetTransformInfo.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/IR/DataLayout.h" +#include "llvm/IR/Dominators.h" #include "llvm/IR/IRBuilder.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/Module.h" @@ -60,6 +60,8 @@ #include "llvm/Transforms/Utils/Local.h" using namespace llvm; +#define DEBUG_TYPE "loop-idiom" + STATISTIC(NumMemSet, "Number of memset's formed from loop stores"); STATISTIC(NumMemCpy, "Number of memcpy's formed from loop load+stores"); @@ -78,9 +80,6 @@ namespace { return dyn_cast<BranchInst>(BB->getTerminator()); } - /// Return the condition of the branch terminating the given basic block. - static Value *getBrCondtion(BasicBlock *); - /// Derive the precondition block (i.e the block that guards the loop /// preheader) from the given preheader. static BasicBlock *getPrecondBb(BasicBlock *PreHead); @@ -108,22 +107,22 @@ namespace { bool preliminaryScreen(); /// Check if the given conditional branch is based on the comparison - /// beween a variable and zero, and if the variable is non-zero, the - /// control yeilds to the loop entry. If the branch matches the behavior, + /// between a variable and zero, and if the variable is non-zero, the + /// control yields to the loop entry. If the branch matches the behavior, /// the variable involved in the comparion is returned. This function will /// be called to see if the precondition and postcondition of the loop /// are in desirable form. - Value *matchCondition (BranchInst *Br, BasicBlock *NonZeroTarget) const; + Value *matchCondition(BranchInst *Br, BasicBlock *NonZeroTarget) const; /// Return true iff the idiom is detected in the loop. and 1) \p CntInst - /// is set to the instruction counting the pupulation bit. 2) \p CntPhi + /// is set to the instruction counting the population bit. 2) \p CntPhi /// is set to the corresponding phi node. 3) \p Var is set to the value /// whose population bits are being counted. bool detectIdiom (Instruction *&CntInst, PHINode *&CntPhi, Value *&Var) const; /// Insert ctpop intrinsic function and some obviously dead instructions. - void transform (Instruction *CntInst, PHINode *CntPhi, Value *Var); + void transform(Instruction *CntInst, PHINode *CntPhi, Value *Var); /// Create llvm.ctpop.* intrinsic function. CallInst *createPopcntIntrinsic(IRBuilderTy &IRB, Value *Val, DebugLoc DL); @@ -131,7 +130,7 @@ namespace { class LoopIdiomRecognize : public LoopPass { Loop *CurLoop; - const DataLayout *TD; + const DataLayout *DL; DominatorTree *DT; ScalarEvolution *SE; TargetLibraryInfo *TLI; @@ -140,10 +139,10 @@ namespace { static char ID; explicit LoopIdiomRecognize() : LoopPass(ID) { initializeLoopIdiomRecognizePass(*PassRegistry::getPassRegistry()); - TD = 0; DT = 0; SE = 0; TLI = 0; TTI = 0; + DL = nullptr; DT = nullptr; SE = nullptr; TLI = nullptr; TTI = nullptr; } - bool runOnLoop(Loop *L, LPPassManager &LPM); + bool runOnLoop(Loop *L, LPPassManager &LPM) override; bool runOnLoopBlock(BasicBlock *BB, const SCEV *BECount, SmallVectorImpl<BasicBlock*> &ExitBlocks); @@ -163,7 +162,7 @@ namespace { /// This transformation requires natural loop information & requires that /// loop preheaders be inserted into the CFG. /// - virtual void getAnalysisUsage(AnalysisUsage &AU) const { + void getAnalysisUsage(AnalysisUsage &AU) const override { AU.addRequired<LoopInfo>(); AU.addPreserved<LoopInfo>(); AU.addRequiredID(LoopSimplifyID); @@ -174,18 +173,23 @@ namespace { AU.addPreserved<AliasAnalysis>(); AU.addRequired<ScalarEvolution>(); AU.addPreserved<ScalarEvolution>(); - AU.addPreserved<DominatorTree>(); - AU.addRequired<DominatorTree>(); + AU.addPreserved<DominatorTreeWrapperPass>(); + AU.addRequired<DominatorTreeWrapperPass>(); AU.addRequired<TargetLibraryInfo>(); AU.addRequired<TargetTransformInfo>(); } const DataLayout *getDataLayout() { - return TD ? TD : TD=getAnalysisIfAvailable<DataLayout>(); + if (DL) + return DL; + DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>(); + DL = DLP ? &DLP->getDataLayout() : nullptr; + return DL; } DominatorTree *getDominatorTree() { - return DT ? DT : (DT=&getAnalysis<DominatorTree>()); + return DT ? DT + : (DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree()); } ScalarEvolution *getScalarEvolution() { @@ -212,7 +216,7 @@ char LoopIdiomRecognize::ID = 0; INITIALIZE_PASS_BEGIN(LoopIdiomRecognize, "loop-idiom", "Recognize loop idioms", false, false) INITIALIZE_PASS_DEPENDENCY(LoopInfo) -INITIALIZE_PASS_DEPENDENCY(DominatorTree) +INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) INITIALIZE_PASS_DEPENDENCY(LoopSimplify) INITIALIZE_PASS_DEPENDENCY(LCSSA) INITIALIZE_PASS_DEPENDENCY(ScalarEvolution) @@ -244,7 +248,7 @@ static void deleteDeadInstruction(Instruction *I, ScalarEvolution &SE, for (unsigned op = 0, e = DeadInst->getNumOperands(); op != e; ++op) { Value *Op = DeadInst->getOperand(op); - DeadInst->setOperand(op, 0); + DeadInst->setOperand(op, nullptr); // If this operand just became dead, add it to the NowDeadInsts list. if (!Op->use_empty()) continue; @@ -286,17 +290,12 @@ bool LIRUtil::isAlmostEmpty(BasicBlock *BB) { return false; } -Value *LIRUtil::getBrCondtion(BasicBlock *BB) { - BranchInst *Br = getBranch(BB); - return Br ? Br->getCondition() : 0; -} - BasicBlock *LIRUtil::getPrecondBb(BasicBlock *PreHead) { if (BasicBlock *BB = PreHead->getSinglePredecessor()) { BranchInst *Br = getBranch(BB); - return Br && Br->isConditional() ? BB : 0; + return Br && Br->isConditional() ? BB : nullptr; } - return 0; + return nullptr; } //===----------------------------------------------------------------------===// @@ -306,7 +305,7 @@ BasicBlock *LIRUtil::getPrecondBb(BasicBlock *PreHead) { //===----------------------------------------------------------------------===// NclPopcountRecognize::NclPopcountRecognize(LoopIdiomRecognize &TheLIR): - LIR(TheLIR), CurLoop(TheLIR.getLoop()), PreCondBB(0) { + LIR(TheLIR), CurLoop(TheLIR.getLoop()), PreCondBB(nullptr) { } bool NclPopcountRecognize::preliminaryScreen() { @@ -343,25 +342,25 @@ bool NclPopcountRecognize::preliminaryScreen() { return true; } -Value *NclPopcountRecognize::matchCondition (BranchInst *Br, - BasicBlock *LoopEntry) const { +Value *NclPopcountRecognize::matchCondition(BranchInst *Br, + BasicBlock *LoopEntry) const { if (!Br || !Br->isConditional()) - return 0; + return nullptr; ICmpInst *Cond = dyn_cast<ICmpInst>(Br->getCondition()); if (!Cond) - return 0; + return nullptr; ConstantInt *CmpZero = dyn_cast<ConstantInt>(Cond->getOperand(1)); if (!CmpZero || !CmpZero->isZero()) - return 0; + return nullptr; ICmpInst::Predicate Pred = Cond->getPredicate(); if ((Pred == ICmpInst::ICMP_NE && Br->getSuccessor(0) == LoopEntry) || (Pred == ICmpInst::ICMP_EQ && Br->getSuccessor(1) == LoopEntry)) return Cond->getOperand(0); - return 0; + return nullptr; } bool NclPopcountRecognize::detectIdiom(Instruction *&CntInst, @@ -392,9 +391,9 @@ bool NclPopcountRecognize::detectIdiom(Instruction *&CntInst, Value *VarX1, *VarX0; PHINode *PhiX, *CountPhi; - DefX2 = CountInst = 0; - VarX1 = VarX0 = 0; - PhiX = CountPhi = 0; + DefX2 = CountInst = nullptr; + VarX1 = VarX0 = nullptr; + PhiX = CountPhi = nullptr; LoopEntry = *(CurLoop->block_begin()); // step 1: Check if the loop-back branch is in desirable form. @@ -441,7 +440,7 @@ bool NclPopcountRecognize::detectIdiom(Instruction *&CntInst, // step 4: Find the instruction which count the population: cnt2 = cnt1 + 1 { - CountInst = NULL; + CountInst = nullptr; for (BasicBlock::iterator Iter = LoopEntry->getFirstNonPHI(), IterE = LoopEntry->end(); Iter != IterE; Iter++) { Instruction *Inst = Iter; @@ -458,9 +457,8 @@ bool NclPopcountRecognize::detectIdiom(Instruction *&CntInst, // Check if the result of the instruction is live of the loop. bool LiveOutLoop = false; - for (Value::use_iterator I = Inst->use_begin(), E = Inst->use_end(); - I != E; I++) { - if ((cast<Instruction>(*I))->getParent() != LoopEntry) { + for (User *U : Inst->users()) { + if ((cast<Instruction>(U))->getParent() != LoopEntry) { LiveOutLoop = true; break; } } @@ -519,7 +517,7 @@ void NclPopcountRecognize::transform(Instruction *CntInst, // TripCnt is exactly the number of iterations the loop has TripCnt = NewCount; - // If the popoulation counter's initial value is not zero, insert Add Inst. + // If the population counter's initial value is not zero, insert Add Inst. Value *CntInitVal = CntPhi->getIncomingValueForBlock(PreHead); ConstantInt *InitConst = dyn_cast<ConstantInt>(CntInitVal); if (!InitConst || !InitConst->isZero()) { @@ -596,11 +594,9 @@ void NclPopcountRecognize::transform(Instruction *CntInst, // __builtin_ctpop(). { SmallVector<Value *, 4> CntUses; - for (Value::use_iterator I = CntInst->use_begin(), E = CntInst->use_end(); - I != E; I++) { - if (cast<Instruction>(*I)->getParent() != Body) - CntUses.push_back(*I); - } + for (User *U : CntInst->users()) + if (cast<Instruction>(U)->getParent() != Body) + CntUses.push_back(U); for (unsigned Idx = 0; Idx < CntUses.size(); Idx++) { (cast<Instruction>(CntUses[Idx]))->replaceUsesOfWith(CntInst, NewCount); } @@ -705,6 +701,9 @@ bool LoopIdiomRecognize::runOnNoncountableLoop() { } bool LoopIdiomRecognize::runOnLoop(Loop *L, LPPassManager &LPM) { + if (skipOptnoneFunction(L)) + return false; + CurLoop = L; // If the loop could not be converted to canonical form, it must have an @@ -746,7 +745,7 @@ bool LoopIdiomRecognize::runOnLoopBlock(BasicBlock *BB, const SCEV *BECount, // If processing the store invalidated our iterator, start over from the // top of the block. - if (InstPtr == 0) + if (!InstPtr) I = BB->begin(); continue; } @@ -759,7 +758,7 @@ bool LoopIdiomRecognize::runOnLoopBlock(BasicBlock *BB, const SCEV *BECount, // If processing the memset invalidated our iterator, start over from the // top of the block. - if (InstPtr == 0) + if (!InstPtr) I = BB->begin(); continue; } @@ -777,7 +776,7 @@ bool LoopIdiomRecognize::processLoopStore(StoreInst *SI, const SCEV *BECount) { Value *StorePtr = SI->getPointerOperand(); // Reject stores that are so large that they overflow an unsigned. - uint64_t SizeInBits = TD->getTypeSizeInBits(StoredVal->getType()); + uint64_t SizeInBits = DL->getTypeSizeInBits(StoredVal->getType()); if ((SizeInBits & 7) || (SizeInBits >> 32) != 0) return false; @@ -786,7 +785,7 @@ bool LoopIdiomRecognize::processLoopStore(StoreInst *SI, const SCEV *BECount) { // random store we can't handle. const SCEVAddRecExpr *StoreEv = dyn_cast<SCEVAddRecExpr>(SE->getSCEV(StorePtr)); - if (StoreEv == 0 || StoreEv->getLoop() != CurLoop || !StoreEv->isAffine()) + if (!StoreEv || StoreEv->getLoop() != CurLoop || !StoreEv->isAffine()) return false; // Check to see if the stride matches the size of the store. If so, then we @@ -794,7 +793,7 @@ bool LoopIdiomRecognize::processLoopStore(StoreInst *SI, const SCEV *BECount) { unsigned StoreSize = (unsigned)SizeInBits >> 3; const SCEVConstant *Stride = dyn_cast<SCEVConstant>(StoreEv->getOperand(1)); - if (Stride == 0 || StoreSize != Stride->getValue()->getValue()) { + if (!Stride || StoreSize != Stride->getValue()->getValue()) { // TODO: Could also handle negative stride here someday, that will require // the validity check in mayLoopAccessLocation to be updated though. // Enable this to print exact negative strides. @@ -843,7 +842,7 @@ processLoopMemSet(MemSetInst *MSI, const SCEV *BECount) { // loop, which indicates a strided store. If we have something else, it's a // random store we can't handle. const SCEVAddRecExpr *Ev = dyn_cast<SCEVAddRecExpr>(SE->getSCEV(Pointer)); - if (Ev == 0 || Ev->getLoop() != CurLoop || !Ev->isAffine()) + if (!Ev || Ev->getLoop() != CurLoop || !Ev->isAffine()) return false; // Reject memsets that are so large that they overflow an unsigned. @@ -857,7 +856,7 @@ processLoopMemSet(MemSetInst *MSI, const SCEV *BECount) { // TODO: Could also handle negative stride here someday, that will require the // validity check in mayLoopAccessLocation to be updated though. - if (Stride == 0 || MSI->getLength() != Stride->getValue()) + if (!Stride || MSI->getLength() != Stride->getValue()) return false; return processLoopStridedStore(Pointer, (unsigned)SizeInBytes, @@ -905,28 +904,28 @@ static bool mayLoopAccessLocation(Value *Ptr,AliasAnalysis::ModRefResult Access, /// /// Note that we don't ever attempt to use memset_pattern8 or 4, because these /// just replicate their input array and then pass on to memset_pattern16. -static Constant *getMemSetPatternValue(Value *V, const DataLayout &TD) { +static Constant *getMemSetPatternValue(Value *V, const DataLayout &DL) { // If the value isn't a constant, we can't promote it to being in a constant // array. We could theoretically do a store to an alloca or something, but // that doesn't seem worthwhile. Constant *C = dyn_cast<Constant>(V); - if (C == 0) return 0; + if (!C) return nullptr; // Only handle simple values that are a power of two bytes in size. - uint64_t Size = TD.getTypeSizeInBits(V->getType()); + uint64_t Size = DL.getTypeSizeInBits(V->getType()); if (Size == 0 || (Size & 7) || (Size & (Size-1))) - return 0; + return nullptr; // Don't care enough about darwin/ppc to implement this. - if (TD.isBigEndian()) - return 0; + if (DL.isBigEndian()) + return nullptr; // Convert to size in bytes. Size /= 8; // TODO: If CI is larger than 16-bytes, we can try slicing it in half to see // if the top and bottom are the same (e.g. for vectors and large integers). - if (Size > 16) return 0; + if (Size > 16) return nullptr; // If the constant is exactly 16 bytes, just use it. if (Size == 16) return C; @@ -951,7 +950,7 @@ processLoopStridedStore(Value *DestPtr, unsigned StoreSize, // are stored. A store of i32 0x01020304 can never be turned into a memset, // but it can be turned into memset_pattern if the target supports it. Value *SplatValue = isBytewiseValue(StoredVal); - Constant *PatternValue = 0; + Constant *PatternValue = nullptr; unsigned DestAS = DestPtr->getType()->getPointerAddressSpace(); @@ -962,13 +961,13 @@ processLoopStridedStore(Value *DestPtr, unsigned StoreSize, // promote the memset. CurLoop->isLoopInvariant(SplatValue)) { // Keep and use SplatValue. - PatternValue = 0; + PatternValue = nullptr; } else if (DestAS == 0 && TLI->has(LibFunc::memset_pattern16) && - (PatternValue = getMemSetPatternValue(StoredVal, *TD))) { + (PatternValue = getMemSetPatternValue(StoredVal, *DL))) { // Don't create memset_pattern16s with address spaces. // It looks like we can use PatternValue! - SplatValue = 0; + SplatValue = nullptr; } else { // Otherwise, this isn't an idiom we can transform. For example, we can't // do anything with a 3-byte store. @@ -1006,7 +1005,7 @@ processLoopStridedStore(Value *DestPtr, unsigned StoreSize, // The # stored bytes is (BECount+1)*Size. Expand the trip count out to // pointer size if it isn't already. - Type *IntPtr = Builder.getIntPtrTy(TD, DestAS); + Type *IntPtr = Builder.getIntPtrTy(DL, DestAS); BECount = SE->getTruncateOrZeroExtend(BECount, IntPtr); const SCEV *NumBytesS = SE->getAddExpr(BECount, SE->getConstant(IntPtr, 1), @@ -1035,7 +1034,7 @@ processLoopStridedStore(Value *DestPtr, unsigned StoreSize, Int8PtrTy, Int8PtrTy, IntPtr, - (void*)0); + (void*)nullptr); // Otherwise we should form a memset_pattern16. PatternValue is known to be // an constant array of 16-bytes. Plop the value into a mergable global. @@ -1120,7 +1119,7 @@ processLoopStoreOfLoopLoad(StoreInst *SI, unsigned StoreSize, // The # stored bytes is (BECount+1)*Size. Expand the trip count out to // pointer size if it isn't already. - Type *IntPtrTy = Builder.getIntPtrTy(TD, SI->getPointerAddressSpace()); + Type *IntPtrTy = Builder.getIntPtrTy(DL, SI->getPointerAddressSpace()); BECount = SE->getTruncateOrZeroExtend(BECount, IntPtrTy); const SCEV *NumBytesS = SE->getAddExpr(BECount, SE->getConstant(IntPtrTy, 1), |