Increment iterator now because IVUseShouldUsePostIncValue may remove

User from the list of I users.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35051 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index fcbf9e301c..ec3fed2f1b 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/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;