diff options
| author | Chris Lattner <sabre@nondot.org> | 2005-06-17 01:45:53 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2005-06-17 01:45:53 +0000 |
| commit | 5e735294bf5d8df67b8947016c675ca899d4fb79 (patch) | |
| tree | ddc2e00ff1150f7379b3d52e8f6e0c59a2396152 /llvm/lib/Transforms/Utils | |
| parent | 29ae6f6ed964d060f22ff7d63a02406240c749fc (diff) | |
| download | bcm5719-llvm-5e735294bf5d8df67b8947016c675ca899d4fb79.tar.gz bcm5719-llvm-5e735294bf5d8df67b8947016c675ca899d4fb79.zip | |
Don't crash on: X = phi (X, X).
This fixes PR584 and Transforms/SimplifyCFG/2005-06-16-PHICrash.ll
llvm-svn: 22232
Diffstat (limited to 'llvm/lib/Transforms/Utils')
| -rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyCFG.cpp | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index ad78506ad42..6a3b803cbdb 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -1461,12 +1461,15 @@ bool llvm::SimplifyCFG(BasicBlock *BB) { BasicBlock::iterator AfterPHIIt = BB->begin(); while (isa<PHINode>(AfterPHIIt)) { PHINode *PN = cast<PHINode>(AfterPHIIt++); - if (PN->getIncomingValue(0) == PN->getIncomingValue(1)) - PN->replaceAllUsesWith(PN->getIncomingValue(0)); - else if (!DominatesMergePoint(PN->getIncomingValue(0), BB, - &AggressiveInsts) || - !DominatesMergePoint(PN->getIncomingValue(1), BB, - &AggressiveInsts)) { + if (PN->getIncomingValue(0) == PN->getIncomingValue(1)) { + if (PN->getIncomingValue(0) != PN) + PN->replaceAllUsesWith(PN->getIncomingValue(0)); + else + PN->replaceAllUsesWith(UndefValue::get(PN->getType())); + } else if (!DominatesMergePoint(PN->getIncomingValue(0), BB, + &AggressiveInsts) || + !DominatesMergePoint(PN->getIncomingValue(1), BB, + &AggressiveInsts)) { CanPromote = false; break; } |
