Don't mark argument value stores as immutable, as otherwise the post-RA

scheduler may reorder loads from them before the stores and other such
badness. PR8347. Patch by David Meyer

llvm-svn: 116602

lib/Target/ARM/ARMISelLowering.cpp

@@ -2217,7 +2217,7 @@ ARMTargetLowering::LowerFormalArguments(SDValue Chain,
       AFI->setVarArgsFrameIndex(
         MFI->CreateFixedObject(VARegSaveSize,
                                ArgOffset + VARegSaveSize - VARegSize,
-                               true));
+                               false));
       SDValue FIN = DAG.getFrameIndex(AFI->getVarArgsFrameIndex(),
                                       getPointerTy());