diff options
Diffstat (limited to 'llvm/lib/Transforms/Scalar/ADCE.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/ADCE.cpp | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/llvm/lib/Transforms/Scalar/ADCE.cpp b/llvm/lib/Transforms/Scalar/ADCE.cpp index 089124a87f8..a2ca367c458 100644 --- a/llvm/lib/Transforms/Scalar/ADCE.cpp +++ b/llvm/lib/Transforms/Scalar/ADCE.cpp @@ -1,14 +1,14 @@ //===- ADCE.cpp - Code to perform aggressive dead code elimination --------===// -// +// // The LLVM Compiler Infrastructure // // This file was developed by the LLVM research group and is distributed under // the University of Illinois Open Source License. See LICENSE.TXT for details. -// +// //===----------------------------------------------------------------------===// // // This file implements "aggressive" dead code elimination. ADCE is DCe where -// values are assumed to be dead until proven otherwise. This is similar to +// values are assumed to be dead until proven otherwise. This is similar to // SCCP, except applied to the liveness of values. // //===----------------------------------------------------------------------===// @@ -116,11 +116,11 @@ void ADCE::markBlockAlive(BasicBlock *BB) { if (It != CDG.end()) { // Get the blocks that this node is control dependent on... const PostDominanceFrontier::DomSetType &CDB = It->second; - for (PostDominanceFrontier::DomSetType::const_iterator I = + for (PostDominanceFrontier::DomSetType::const_iterator I = CDB.begin(), E = CDB.end(); I != E; ++I) markTerminatorLive(*I); // Mark all their terminators as live } - + // If this basic block is live, and it ends in an unconditional branch, then // the branch is alive as well... if (BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator())) @@ -162,7 +162,7 @@ TerminatorInst *ADCE::convertToUnconditionalBranch(TerminatorInst *TI) { // Remove entries from PHI nodes to avoid confusing ourself later... for (unsigned i = 1, e = TI->getNumSuccessors(); i != e; ++i) TI->getSuccessor(i)->removePredecessor(BB); - + // Delete the old branch itself... BB->getInstList().erase(TI); return NB; @@ -203,7 +203,7 @@ bool ADCE::doADCE() { } // Iterate over all of the instructions in the function, eliminating trivially - // dead instructions, and marking instructions live that are known to be + // dead instructions, and marking instructions live that are known to be // needed. Perform the walk in depth first order so that we avoid marking any // instructions live in basic blocks that are unreachable. These blocks will // be eliminated later, along with the instructions inside. @@ -338,7 +338,7 @@ bool ADCE::doADCE() { return MadeChanges; } - + // If the entry node is dead, insert a new entry node to eliminate the entry // node as a special case. @@ -350,7 +350,7 @@ bool ADCE::doADCE() { AliveBlocks.insert(NewEntry); // This block is always alive! LiveSet.insert(NewEntry->getTerminator()); // The branch is live } - + // Loop over all of the alive blocks in the function. If any successor // blocks are not alive, we adjust the outgoing branches to branch to the // first live postdominator of the live block, adjusting any PHI nodes in @@ -360,7 +360,7 @@ bool ADCE::doADCE() { if (AliveBlocks.count(I)) { BasicBlock *BB = I; TerminatorInst *TI = BB->getTerminator(); - + // If the terminator instruction is alive, but the block it is contained // in IS alive, this means that this terminator is a conditional branch on // a condition that doesn't matter. Make it an unconditional branch to @@ -392,7 +392,7 @@ bool ADCE::doADCE() { break; } } - } + } // There is a special case here... if there IS no post-dominator for // the block we have nowhere to point our branch to. Instead, convert @@ -411,12 +411,12 @@ bool ADCE::doADCE() { // branch into an infinite loop into a return instruction! // RemoveSuccessor(TI, i); - + // RemoveSuccessor may replace TI... make sure we have a fresh // pointer. // TI = BB->getTerminator(); - + // Rescan this successor... --i; } else { @@ -443,7 +443,7 @@ bool ADCE::doADCE() { int OldIdx = PN->getBasicBlockIndex(LastDead); assert(OldIdx != -1 &&"LastDead is not a pred of NextAlive!"); Value *InVal = PN->getIncomingValue(OldIdx); - + // Add an incoming value for BB now... PN->addIncoming(InVal, BB); } |
