don't delete the last store to an alloca if the store is volatile.

llvm-svn: 50390

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
index 655ab102599..c707e6ee670 100644
--- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -10311,7 +10311,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
   
   // If the RHS is an alloca with a single use, zapify the store, making the
   // alloca dead.
-  if (Ptr->hasOneUse()) {
+  if (Ptr->hasOneUse() && !SI.isVolatile()) {
     if (isa<AllocaInst>(Ptr)) {
       EraseInstFromFunction(SI);
       ++NumCombined;