diff options
| author | Nadav Rotem <nrotem@apple.com> | 2012-12-30 07:47:00 +0000 |
|---|---|---|
| committer | Nadav Rotem <nrotem@apple.com> | 2012-12-30 07:47:00 +0000 |
| commit | db2367512e87dbd7b93c3250ef30c9df5e40cb43 (patch) | |
| tree | e5e199e109705e5cd36224f6db77c8b8adb13074 /lib/Transforms | |
| parent | a6542923b8ad94d791a12d3d5ae3e62a611f0383 (diff) | |
LoopVectorizer: Fix a bug in the code that updates the loop exiting block.
LCSSA PHIs may have undef values. The vectorizer updates values that are used by outside users such as PHIs.
The bug happened because undefs are not loop values. This patch handles these PHIs.
PR14725
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171251 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms')
| -rw-r--r-- | lib/Transforms/Vectorize/LoopVectorize.cpp | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp index 7fb9bbada0..653c111182 100644 --- a/lib/Transforms/Vectorize/LoopVectorize.cpp +++ b/lib/Transforms/Vectorize/LoopVectorize.cpp @@ -909,6 +909,19 @@ InnerLoopVectorizer::vectorizeLoop(LoopVectorizationLegality *Legal) { (RdxPhi)->setIncomingValue(SelfEdgeBlockIdx, Scalar0); (RdxPhi)->setIncomingValue(IncomingEdgeBlockIdx, RdxDesc.LoopExitInstr); }// end of for each redux variable. + + // The Loop exit block may have single value PHI nodes where the incoming + // value is 'undef'. While vectorizing we only handled real values that + // were defined inside the loop. Here we handle the 'undef case'. + // See PR14725. + for (BasicBlock::iterator LEI = LoopExitBlock->begin(), + LEE = LoopExitBlock->end(); LEI != LEE; ++LEI) { + PHINode *LCSSAPhi = dyn_cast<PHINode>(LEI); + if (!LCSSAPhi) continue; + if (LCSSAPhi->getNumIncomingValues() == 1) + LCSSAPhi->addIncoming(UndefValue::get(LCSSAPhi->getType()), + LoopMiddleBlock); + } } Value *InnerLoopVectorizer::createEdgeMask(BasicBlock *Src, BasicBlock *Dst) { |