diff options
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp')
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp | 82 |
1 files changed, 41 insertions, 41 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp index 337cfe3..e2d7966 100644 --- a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp +++ b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp @@ -69,8 +69,8 @@ isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy, if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) { // If the GEP has all zero indices, it doesn't offset the pointer. If it // doesn't, it does. - if (!isOnlyCopiedFromConstantGlobal(GEP, TheCopy, ToDelete, - IsOffset || !GEP->hasAllZeroIndices())) + if (!isOnlyCopiedFromConstantGlobal( + GEP, TheCopy, ToDelete, IsOffset || !GEP->hasAllZeroIndices())) return false; continue; } @@ -166,7 +166,7 @@ Instruction *InstCombiner::visitAllocaInst(AllocaInst &AI) { // Convert: alloca Ty, C - where C is a constant != 1 into: alloca [C x Ty], 1 if (AI.isArrayAllocation()) { // Check C != 1 if (const ConstantInt *C = dyn_cast<ConstantInt>(AI.getArraySize())) { - Type *NewTy = + Type *NewTy = ArrayType::get(AI.getAllocatedType(), C->getZExtValue()); AllocaInst *New = Builder->CreateAlloca(NewTy, 0, AI.getName()); New->setAlignment(AI.getAlignment()); @@ -294,7 +294,7 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI, Type *SrcPTy = SrcTy->getElementType(); - if (DestPTy->isIntegerTy() || DestPTy->isPointerTy() || + if (DestPTy->isIntegerTy() || DestPTy->isPointerTy() || DestPTy->isVectorTy()) { // If the source is an array, the code below will not succeed. Check to // see if a trivial 'gep P, 0, 0' will help matters. Only do this for @@ -311,7 +311,7 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI, } if (IC.getDataLayout() && - (SrcPTy->isIntegerTy() || SrcPTy->isPointerTy() || + (SrcPTy->isIntegerTy() || SrcPTy->isPointerTy() || SrcPTy->isVectorTy()) && // Do not allow turning this into a load of an integer, which is then // casted to a pointer, this pessimizes pointer analysis a lot. @@ -322,7 +322,7 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI, // Okay, we are casting from one integer or pointer type to another of // the same size. Instead of casting the pointer before the load, cast // the result of the loaded value. - LoadInst *NewLoad = + LoadInst *NewLoad = IC.Builder->CreateLoad(CastOp, LI.isVolatile(), CI->getName()); NewLoad->setAlignment(LI.getAlignment()); NewLoad->setAtomic(LI.getOrdering(), LI.getSynchScope()); @@ -359,7 +359,7 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { // None of the following transforms are legal for volatile/atomic loads. // FIXME: Some of it is okay for atomic loads; needs refactoring. if (!LI.isSimple()) return 0; - + // Do really simple store-to-load forwarding and load CSE, to catch cases // where there are several consecutive memory accesses to the same location, // separated by a few arithmetic operations. @@ -380,7 +380,7 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { Constant::getNullValue(Op->getType()), &LI); return ReplaceInstUsesWith(LI, UndefValue::get(LI.getType())); } - } + } // load null/undef -> unreachable // TODO: Consider a target hook for valid address spaces for this xform. @@ -399,7 +399,7 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { if (CE->isCast()) if (Instruction *Res = InstCombineLoadCast(*this, LI, TD)) return Res; - + if (Op->hasOneUse()) { // Change select and PHI nodes to select values instead of addresses: this // helps alias analysis out a lot, allows many others simplifications, and @@ -453,18 +453,18 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { Type *DestPTy = cast<PointerType>(CI->getType())->getElementType(); PointerType *SrcTy = dyn_cast<PointerType>(CastOp->getType()); if (SrcTy == 0) return 0; - + Type *SrcPTy = SrcTy->getElementType(); if (!DestPTy->isIntegerTy() && !DestPTy->isPointerTy()) return 0; - + /// NewGEPIndices - If SrcPTy is an aggregate type, we can emit a "noop gep" /// to its first element. This allows us to handle things like: /// store i32 xxx, (bitcast {foo*, float}* %P to i32*) /// on 32-bit hosts. SmallVector<Value*, 4> NewGEPIndices; - + // If the source is an array, the code below will not succeed. Check to // see if a trivial 'gep P, 0, 0' will help matters. Only do this for // constants. @@ -472,7 +472,7 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { // Index through pointer. Constant *Zero = Constant::getNullValue(Type::getInt32Ty(SI.getContext())); NewGEPIndices.push_back(Zero); - + while (1) { if (StructType *STy = dyn_cast<StructType>(SrcPTy)) { if (!STy->getNumElements()) /* Struct can be empty {} */ @@ -486,24 +486,24 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { break; } } - + SrcTy = PointerType::get(SrcPTy, SrcTy->getAddressSpace()); } if (!SrcPTy->isIntegerTy() && !SrcPTy->isPointerTy()) return 0; - + // If the pointers point into different address spaces or if they point to // values with different sizes, we can't do the transformation. if (!IC.getDataLayout() || - SrcTy->getAddressSpace() != + SrcTy->getAddressSpace() != cast<PointerType>(CI->getType())->getAddressSpace() || IC.getDataLayout()->getTypeSizeInBits(SrcPTy) != IC.getDataLayout()->getTypeSizeInBits(DestPTy)) return 0; // Okay, we are casting from one integer or pointer type to another of - // the same size. Instead of casting the pointer before + // the same size. Instead of casting the pointer before // the store, cast the value to be stored. Value *NewCast; Value *SIOp0 = SI.getOperand(0); @@ -517,12 +517,12 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { if (SIOp0->getType()->isPointerTy()) opcode = Instruction::PtrToInt; } - + // SIOp0 is a pointer to aggregate and this is a store to the first field, // emit a GEP to index into its first field. if (!NewGEPIndices.empty()) CastOp = IC.Builder->CreateInBoundsGEP(CastOp, NewGEPIndices); - + NewCast = IC.Builder->CreateCast(opcode, SIOp0, CastDstTy, SIOp0->getName()+".c"); SI.setOperand(0, NewCast); @@ -541,7 +541,7 @@ static Instruction *InstCombineStoreToCast(InstCombiner &IC, StoreInst &SI) { static bool equivalentAddressValues(Value *A, Value *B) { // Test if the values are trivially equivalent. if (A == B) return true; - + // Test if the values come form identical arithmetic instructions. // This uses isIdenticalToWhenDefined instead of isIdenticalTo because // its only used to compare two uses within the same basic block, which @@ -554,7 +554,7 @@ static bool equivalentAddressValues(Value *A, Value *B) { if (Instruction *BI = dyn_cast<Instruction>(B)) if (cast<Instruction>(A)->isIdenticalToWhenDefined(BI)) return true; - + // Otherwise they may not be equivalent. return false; } @@ -585,7 +585,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { // If the RHS is an alloca with a single use, zapify the store, making the // alloca dead. if (Ptr->hasOneUse()) { - if (isa<AllocaInst>(Ptr)) + if (isa<AllocaInst>(Ptr)) return EraseInstFromFunction(SI); if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) { if (isa<AllocaInst>(GEP->getOperand(0))) { @@ -608,8 +608,8 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { (isa<BitCastInst>(BBI) && BBI->getType()->isPointerTy())) { ScanInsts++; continue; - } - + } + if (StoreInst *PrevSI = dyn_cast<StoreInst>(BBI)) { // Prev store isn't volatile, and stores to the same location? if (PrevSI->isSimple() && equivalentAddressValues(PrevSI->getOperand(1), @@ -621,7 +621,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { } break; } - + // If this is a load, we have to stop. However, if the loaded value is from // the pointer we're loading and is producing the pointer we're storing, // then *this* store is dead (X = load P; store X -> P). @@ -629,12 +629,12 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { if (LI == Val && equivalentAddressValues(LI->getOperand(0), Ptr) && LI->isSimple()) return EraseInstFromFunction(SI); - + // Otherwise, this is a load from some other location. Stores before it // may not be dead. break; } - + // Don't skip over loads or things that can modify memory. if (BBI->mayWriteToMemory() || BBI->mayReadFromMemory()) break; @@ -664,11 +664,11 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { if (Instruction *Res = InstCombineStoreToCast(*this, SI)) return Res; - + // If this store is the last instruction in the basic block (possibly // excepting debug info instructions), and if the block ends with an // unconditional branch, try to move it to the successor block. - BBI = &SI; + BBI = &SI; do { ++BBI; } while (isa<DbgInfoIntrinsic>(BBI) || @@ -677,7 +677,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { if (BI->isUnconditional()) if (SimplifyStoreAtEndOfBlock(SI)) return 0; // xform done! - + return 0; } @@ -691,12 +691,12 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) { /// bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { BasicBlock *StoreBB = SI.getParent(); - + // Check to see if the successor block has exactly two incoming edges. If // so, see if the other predecessor contains a store to the same location. // if so, insert a PHI node (if needed) and move the stores down. BasicBlock *DestBB = StoreBB->getTerminator()->getSuccessor(0); - + // Determine whether Dest has exactly two predecessors and, if so, compute // the other predecessor. pred_iterator PI = pred_begin(DestBB); @@ -708,7 +708,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { if (++PI == pred_end(DestBB)) return false; - + P = *PI; if (P != StoreBB) { if (OtherBB) @@ -728,7 +728,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { BranchInst *OtherBr = dyn_cast<BranchInst>(BBI); if (!OtherBr || BBI == OtherBB->begin()) return false; - + // If the other block ends in an unconditional branch, check for the 'if then // else' case. there is an instruction before the branch. StoreInst *OtherStore = 0; @@ -750,10 +750,10 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { } else { // Otherwise, the other block ended with a conditional branch. If one of the // destinations is StoreBB, then we have the if/then case. - if (OtherBr->getSuccessor(0) != StoreBB && + if (OtherBr->getSuccessor(0) != StoreBB && OtherBr->getSuccessor(1) != StoreBB) return false; - + // Okay, we know that OtherBr now goes to Dest and StoreBB, so this is an // if/then triangle. See if there is a store to the same ptr as SI that // lives in OtherBB. @@ -771,7 +771,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { BBI == OtherBB->begin()) return false; } - + // In order to eliminate the store in OtherBr, we have to // make sure nothing reads or overwrites the stored value in // StoreBB. @@ -781,7 +781,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { return false; } } - + // Insert a PHI node now if we need it. Value *MergedVal = OtherStore->getOperand(0); if (MergedVal != SI.getOperand(0)) { @@ -790,7 +790,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { PN->addIncoming(OtherStore->getOperand(0), OtherBB); MergedVal = InsertNewInstBefore(PN, DestBB->front()); } - + // Advance to a place where it is safe to insert the new store and // insert it. BBI = DestBB->getFirstInsertionPt(); @@ -800,7 +800,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { SI.getOrdering(), SI.getSynchScope()); InsertNewInstBefore(NewSI, *BBI); - NewSI->setDebugLoc(OtherStore->getDebugLoc()); + NewSI->setDebugLoc(OtherStore->getDebugLoc()); // If the two stores had the same TBAA tag, preserve it. if (MDNode *TBAATag = SI.getMetadata(LLVMContext::MD_tbaa)) @@ -808,7 +808,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { OtherStore->getMetadata(LLVMContext::MD_tbaa)))) NewSI->setMetadata(LLVMContext::MD_tbaa, TBAATag); - + // Nuke the old stores. EraseInstFromFunction(SI); EraseInstFromFunction(*OtherStore); |