diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp | 25 |
1 files changed, 8 insertions, 17 deletions
diff --git a/contrib/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/contrib/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp index ec625b4..093083a 100644 --- a/contrib/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp +++ b/contrib/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp @@ -97,23 +97,13 @@ bool llvm::DeleteDeadPHIs(BasicBlock *BB) { /// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor, /// if possible. The return value indicates success or failure. bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, Pass *P) { - pred_iterator PI(pred_begin(BB)), PE(pred_end(BB)); - // Can't merge the entry block. Don't merge away blocks who have their - // address taken: this is a bug if the predecessor block is the entry node - // (because we'd end up taking the address of the entry) and undesirable in - // any case. - if (pred_begin(BB) == pred_end(BB) || - BB->hasAddressTaken()) return false; + // Don't merge away blocks who have their address taken. + if (BB->hasAddressTaken()) return false; - BasicBlock *PredBB = *PI++; - for (; PI != PE; ++PI) // Search all predecessors, see if they are all same - if (*PI != PredBB) { - PredBB = 0; // There are multiple different predecessors... - break; - } - - // Can't merge if there are multiple predecessors. + // Can't merge if there are multiple predecessors, or no predecessors. + BasicBlock *PredBB = BB->getUniquePredecessor(); if (!PredBB) return false; + // Don't break self-loops. if (PredBB == BB) return false; // Don't break invokes. @@ -267,7 +257,7 @@ void llvm::RemoveSuccessor(TerminatorInst *TI, unsigned SuccNum) { case Instruction::Switch: // Should remove entry default: case Instruction::Ret: // Cannot happen, has no successors! - llvm_unreachable("Unhandled terminator instruction type in RemoveSuccessor!"); + llvm_unreachable("Unhandled terminator inst type in RemoveSuccessor!"); } if (NewTI) // If it's a different instruction, replace. @@ -421,7 +411,8 @@ BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB, DominatorTree *DT = P ? P->getAnalysisIfAvailable<DominatorTree>() : 0; if (DT) DT->splitBlock(NewBB); - if (DominanceFrontier *DF = P ? P->getAnalysisIfAvailable<DominanceFrontier>():0) + if (DominanceFrontier *DF = + P ? P->getAnalysisIfAvailable<DominanceFrontier>() : 0) DF->splitBlock(NewBB); // Insert a new PHI node into NewBB for every PHI node in BB and that new PHI |
