Like the comment says, do not insert cast instructions before phi nodes

llvm-svn: 22586

1 files changed, 4 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index fcb7ad3dfde..33714a2ad20 100644
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -232,6 +232,10 @@ void LoopStrengthReduce::AnalyzeGetElementPtrUsers(GetElementPtrInst *GEP,
         else
           ++InsertPt;
       }
+      
+      // Do not insert casts into the middle of PHI node blocks.
+      while (isa<PHINode>(InsertPt)) ++InsertPt;
+      
       BP = new CastInst(GEP->getOperand(0), UIntPtrTy,
                         GEP->getOperand(0)->getName(), InsertPt);
     }