From 097632eae39185e56b22598e4037cee885d9643b Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 29 Apr 2002 01:58:47 +0000 Subject: [PATCH] More cleanups git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2392 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../Scalar/DecomposeMultiDimRefs.cpp | 113 +++++++++--------- 1 file changed, 54 insertions(+), 59 deletions(-) diff --git a/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp b/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp index f4bb51a02d1..0367348ef5d 100644 --- a/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp +++ b/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp @@ -1,11 +1,10 @@ //===- llvm/Transforms/DecomposeMultiDimRefs.cpp - Lower array refs to 1D -===// // -// DecomposeMultiDimRefs - -// Convert multi-dimensional references consisting of any combination -// of 2 or more array and structure indices into a sequence of -// instructions (using getelementpr and cast) so that each instruction -// has at most one index (except structure references, -// which need an extra leading index of [0]). +// DecomposeMultiDimRefs - Convert multi-dimensional references consisting of +// any combination of 2 or more array and structure indices into a sequence of +// instructions (using getelementpr and cast) so that each instruction has at +// most one index (except structure references, which need an extra leading +// index of [0]). // //===----------------------------------------------------------------------===// @@ -36,7 +35,6 @@ Pass *createDecomposeMultiDimRefsPass() { // bool DecomposePass::runOnBasicBlock(BasicBlock *BB) { bool Changed = false; - for (BasicBlock::iterator II = BB->begin(); II != BB->end(); ) { if (MemAccessInst *MAI = dyn_cast(*II)) { if (MAI->getNumOperands() > MAI->getFirstIndexOperandNumber()+1) { @@ -63,21 +61,21 @@ bool DecomposePass::runOnBasicBlock(BasicBlock *BB) { // uses the last ptr2 generated in the loop and a single index. // If any index is (uint) 0, we omit the getElementPtr instruction. // -void DecomposePass::decomposeArrayRef(BasicBlock::iterator &BBI){ - MemAccessInst *memI = cast(*BBI); - BasicBlock* BB = memI->getParent(); - Value* lastPtr = memI->getPointerOperand(); +void DecomposePass::decomposeArrayRef(BasicBlock::iterator &BBI) { + MemAccessInst *MAI = cast(*BBI); + BasicBlock *BB = MAI->getParent(); + Value *LastPtr = MAI->getPointerOperand(); // Remove the instruction from the stream BB->getInstList().remove(BBI); - vector newIvec; + vector NewInsts; // Process each index except the last one. // - User::const_op_iterator OI = memI->idx_begin(), OE = memI->idx_end(); - for (; OI != OE && OI+1 != OE; ++OI) { - assert(isa(lastPtr->getType())); + User::const_op_iterator OI = MAI->idx_begin(), OE = MAI->idx_end(); + for (; OI+1 != OE; ++OI) { + assert(isa(LastPtr->getType())); // Check for a zero index. This will need a cast instead of // a getElementPtr, or it may need neither. @@ -87,85 +85,82 @@ void DecomposePass::decomposeArrayRef(BasicBlock::iterator &BBI){ // Extract the first index. If the ptr is a pointer to a structure // and the next index is a structure offset (i.e., not an array offset), // we need to include an initial [0] to index into the pointer. - vector idxVec(1, *OI); - PointerType* ptrType = cast(lastPtr->getType()); - if (isa(ptrType->getElementType()) - && ! ptrType->indexValid(*OI)) - idxVec.insert(idxVec.begin(), ConstantUInt::get(Type::UIntTy, 0)); - + // + vector Indices; + PointerType *PtrTy = cast(LastPtr->getType()); + if (isa(PtrTy->getElementType()) + && !PtrTy->indexValid(*OI)) + Indices.push_back(Constant::getNullValue(Type::UIntTy)); + Indices.push_back(*OI); + // Get the type obtained by applying the first index. // It must be a structure or array. - const Type* nextType = MemAccessInst::getIndexedType(lastPtr->getType(), - idxVec, true); - assert(isa(nextType) || isa(nextType)); + const Type *NextTy = MemAccessInst::getIndexedType(LastPtr->getType(), + Indices, true); + assert(isa(NextTy)); // Get a pointer to the structure or to the elements of the array. - const Type* nextPtrType = - PointerType::get(isa(nextType) ? nextType - : cast(nextType)->getElementType()); + const Type *NextPtrTy = + PointerType::get(isa(NextTy) ? NextTy + : cast(NextTy)->getElementType()); - // Instruction 1: nextPtr1 = GetElementPtr lastPtr, idxVec + // Instruction 1: nextPtr1 = GetElementPtr LastPtr, Indices // This is not needed if the index is zero. - Value *gepValue; - if (indexIsZero) - gepValue = lastPtr; - else { - gepValue = new GetElementPtrInst(lastPtr, idxVec,"ptr1"); - newIvec.push_back(cast(gepValue)); + if (!indexIsZero) { + LastPtr = new GetElementPtrInst(LastPtr, Indices, "ptr1"); + NewInsts.push_back(cast(LastPtr)); } - // Instruction 2: nextPtr2 = cast nextPtr1 to nextPtrType + // Instruction 2: nextPtr2 = cast nextPtr1 to NextPtrTy // This is not needed if the two types are identical. - Value *castInst; - if (gepValue->getType() == nextPtrType) - castInst = gepValue; - else { - castInst = new CastInst(gepValue, nextPtrType, "ptr2"); - newIvec.push_back(cast(castInst)); + // + if (LastPtr->getType() != NextPtrTy) { + LastPtr = new CastInst(LastPtr, NextPtrTy, "ptr2"); + NewInsts.push_back(cast(LastPtr)); } - - lastPtr = castInst; } // // Now create a new instruction to replace the original one // - PointerType *ptrType = cast(lastPtr->getType()); + PointerType *PtrTy = cast(LastPtr->getType()); // First, get the final index vector. As above, we may need an initial [0]. - vector idxVec(1, *OI); - if (isa(ptrType->getElementType()) - && !ptrType->indexValid(*OI)) - idxVec.insert(idxVec.begin(), Constant::getNullValue(Type::UIntTy)); - - Instruction* newInst = NULL; - switch(memI->getOpcode()) { + vector Indices; + if (isa(PtrTy->getElementType()) + && !PtrTy->indexValid(*OI)) + Indices.push_back(Constant::getNullValue(Type::UIntTy)); + + Indices.push_back(*OI); + + Instruction *NewI = 0; + switch(MAI->getOpcode()) { case Instruction::Load: - newInst = new LoadInst(lastPtr, idxVec, memI->getName()); + NewI = new LoadInst(LastPtr, Indices, MAI->getName()); break; case Instruction::Store: - newInst = new StoreInst(memI->getOperand(0), lastPtr, idxVec); + NewI = new StoreInst(MAI->getOperand(0), LastPtr, Indices); break; case Instruction::GetElementPtr: - newInst = new GetElementPtrInst(lastPtr, idxVec, memI->getName()); + NewI = new GetElementPtrInst(LastPtr, Indices, MAI->getName()); break; default: assert(0 && "Unrecognized memory access instruction"); } - newIvec.push_back(newInst); + NewInsts.push_back(NewI); // Replace all uses of the old instruction with the new - memI->replaceAllUsesWith(newInst); + MAI->replaceAllUsesWith(NewI); // Now delete the old instruction... - delete memI; + delete MAI; // Convert our iterator into an index... that cannot get invalidated unsigned ItOffs = BBI-BB->begin(); // Insert all of the new instructions... - BB->getInstList().insert(BBI, newIvec.begin(), newIvec.end()); + BB->getInstList().insert(BBI, NewInsts.begin(), NewInsts.end()); // Advance the iterator to the instruction following the one just inserted... - BBI = BB->begin() + (ItOffs+newIvec.size()); + BBI = BB->begin() + ItOffs + NewInsts.size(); }