Increment iterator now because IVUseShouldUsePostIncValue may remove

User from the list of I users.

llvm-svn: 35051

1 files changed, 6 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index fcbf9e301cf..ec3fed2f1ba 100644
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -400,10 +400,14 @@ bool LoopStrengthReduce::AddUsersIfInteresting(Instruction *I, Loop *L,
   SCEVHandle Stride = Start;
   if (!getSCEVStartAndStride(ISE, L, Start, Stride))
     return false;  // Non-reducible symbolic expression, bail out.
-  
-  for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;++UI){
+
+  for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;) {
     Instruction *User = cast<Instruction>(*UI);
 
+    // Increment iterator now because IVUseShouldUsePostIncValue may remove 
+    // User from the list of I users.
+    ++UI;
+
     // Do not infinitely recurse on PHI nodes.
     if (isa<PHINode>(User) && Processed.count(User))
       continue;