Make instcombine's DSE respect loads as well as stores. It is not safe to

delete the first store in:

store x -> p
load p
store y -> p

This is for PR2297.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50859 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index a3340a0d82..b0ea9f5c43 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -10426,7 +10426,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
     }
     
     // Don't skip over loads or things that can modify memory.
-    if (BBI->mayWriteToMemory())
+    if (BBI->mayWriteToMemory() || BBI->mayReadFromMemory())
       break;
   }