Fix for PR14739. It's not safe to fold a load into a call across a store. Thanks to Nick Lewycky for the initial patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171665 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index c1eaa0e..935f9bd 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -420,6 +420,11 @@
if (!Chain.getNumOperands())
return false;
+ // Since we are not checking for AA here, conservatively abort if the chain
+ // writes to memory. It's not safe to move the callee (a load) across a store.
+ if (isa<MemSDNode>(Chain.getNode()) &&
+ cast<MemSDNode>(Chain.getNode())->writeMem())
+ return false;
if (Chain.getOperand(0).getNode() == Callee.getNode())
return true;
if (Chain.getOperand(0).getOpcode() == ISD::TokenFactor &&