diff options
Diffstat (limited to 'lib/Transforms/Scalar/LoopIdiomRecognize.cpp')
-rw-r--r-- | lib/Transforms/Scalar/LoopIdiomRecognize.cpp | 65 |
1 files changed, 33 insertions, 32 deletions
diff --git a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp index e5e8b84..26a83df 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" @@ -61,6 +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"); @@ -114,7 +115,7 @@ namespace { 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 @@ -138,7 +139,7 @@ namespace { static char ID; explicit LoopIdiomRecognize() : LoopPass(ID) { initializeLoopIdiomRecognizePass(*PassRegistry::getPassRegistry()); - DL = 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) override; @@ -182,7 +183,7 @@ namespace { if (DL) return DL; DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>(); - DL = DLP ? &DLP->getDataLayout() : 0; + DL = DLP ? &DLP->getDataLayout() : nullptr; return DL; } @@ -247,7 +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; @@ -292,9 +293,9 @@ bool LIRUtil::isAlmostEmpty(BasicBlock *BB) { 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; } //===----------------------------------------------------------------------===// @@ -304,7 +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() { @@ -341,25 +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, @@ -390,9 +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. @@ -439,7 +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; @@ -744,7 +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; } @@ -757,7 +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; } @@ -784,7 +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 @@ -792,7 +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. @@ -841,7 +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. @@ -855,7 +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, @@ -908,23 +909,23 @@ static Constant *getMemSetPatternValue(Value *V, const DataLayout &DL) { // 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 = 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 (DL.isBigEndian()) - return 0; + 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; @@ -949,7 +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(); @@ -960,13 +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, *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. @@ -1033,7 +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. |