From 091e440568ed600aef243fd7738d50bf140ce2b3 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Thu, 25 Jun 2009 00:22:44 +0000 Subject: [PATCH] Reword a few comments. llvm-svn: 74146 --- llvm/lib/Transforms/Scalar/LoopRotation.cpp | 34 ++++++++++----------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/llvm/lib/Transforms/Scalar/LoopRotation.cpp b/llvm/lib/Transforms/Scalar/LoopRotation.cpp index a0882301332d..ae9ab95ca784 100644 --- a/llvm/lib/Transforms/Scalar/LoopRotation.cpp +++ b/llvm/lib/Transforms/Scalar/LoopRotation.cpp @@ -108,7 +108,7 @@ static RegisterPass X("loop-rotate", "Rotate Loops"); Pass *llvm::createLoopRotatePass() { return new LoopRotate(); } /// Rotate Loop L as many times as possible. Return true if -/// loop is rotated at least once. +/// the loop is rotated at least once. bool LoopRotate::runOnLoop(Loop *Lp, LPPassManager &LPM) { bool RotatedOneLoop = false; @@ -132,15 +132,15 @@ bool LoopRotate::rotateLoop(Loop *Lp, LPPassManager &LPM) { OrigPreHeader = L->getLoopPreheader(); OrigLatch = L->getLoopLatch(); - // If loop has only one block then there is not much to rotate. + // If the loop has only one block then there is not much to rotate. if (L->getBlocks().size() == 1) return false; assert(OrigHeader && OrigLatch && OrigPreHeader && "Loop is not in canonical form"); - // If loop header is not one of the loop exit block then - // either this loop is already rotated or it is not + // If the loop header is not one of the loop exiting blocks then + // either this loop is already rotated or it is not // suitable for loop rotation transformations. if (!L->isLoopExit(OrigHeader)) return false; @@ -189,19 +189,19 @@ bool LoopRotate::rotateLoop(Loop *Lp, LPPassManager &LPM) { assert(L->contains(NewHeader) && !L->contains(Exit) && "Unable to determine loop header and exit blocks"); - // This code assumes that new header has exactly one predecessor. Remove any - // single entry PHI nodes in it. + // This code assumes that the new header has exactly one predecessor. + // Remove any single-entry PHI nodes in it. assert(NewHeader->getSinglePredecessor() && "New header doesn't have one pred!"); FoldSingleEntryPHINodes(NewHeader); - // Copy PHI nodes and other instructions from original header - // into original pre-header. Unlike original header, original pre-header is - // not a member of loop. + // Copy PHI nodes and other instructions from the original header + // into the original pre-header. Unlike the original header, the original + // pre-header is not a member of the loop. // - // New loop header is one and only successor of original header that + // The new loop header is the one and only successor of original header that // is inside the loop. All other original header successors are outside - // the loop. Copy PHI Nodes from original header into new loop header. + // the loop. Copy PHI Nodes from the original header into the new loop header. // Add second incoming value, from original loop pre-header into these phi // nodes. If a value defined in original header is used outside original // header then new loop header will need new phi nodes with two incoming @@ -218,8 +218,8 @@ bool LoopRotate::rotateLoop(Loop *Lp, LPPassManager &LPM) { // are directly propagated. Value *NPV = PN->getIncomingValueForBlock(OrigPreHeader); - // Create new PHI node with two incoming values for NewHeader. - // One incoming value is from OrigLatch (through OrigHeader) and + // Create a new PHI node with two incoming values for NewHeader. + // One incoming value is from OrigLatch (through OrigHeader) and the // second incoming value is from original pre-header. PHINode *NH = PHINode::Create(PN->getType(), PN->getName(), NewHeader->begin()); @@ -334,8 +334,8 @@ bool LoopRotate::rotateLoop(Loop *Lp, LPPassManager &LPM) { // Add second incoming argument from new Pre header. UPhi->addIncoming(ILoopHeaderInfo.PreHeader, OrigPreHeader); } else { - // Used outside Exit block. Create a new PHI node from exit block - // to receive value from ne new header ane pre header. + // Used outside Exit block. Create a new PHI node in the exit block + // to receive the value from the new header and pre-header. PHINode *PN = PHINode::Create(U->getType(), U->getName(), Exit->begin()); PN->addIncoming(ILoopHeaderInfo.PreHeader, OrigPreHeader); @@ -367,8 +367,8 @@ bool LoopRotate::rotateLoop(Loop *Lp, LPPassManager &LPM) { } /// Make sure all Exit block PHINodes have required incoming values. -/// If incoming value is constant or defined outside the loop then -/// PHINode may not have an entry for original pre-header. +/// If an incoming value is constant or defined outside the loop then +/// PHINode may not have an entry for the original pre-header. void LoopRotate::updateExitBlock() { for (BasicBlock::iterator I = Exit->begin(), E = Exit->end();