Fix a bug in x86's PreprocessForRMW logic that was exposed
by aggressive chain operand optimization. UpdateNodeOperands
does not modify the node in place if it would result in
a node identical to an existing node.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78297 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index e1344da..7340d7f 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -342,9 +342,11 @@
Ops.push_back(Load.getOperand(0));
else
Ops.push_back(TF.getOperand(i));
- CurDAG->UpdateNodeOperands(TF, &Ops[0], Ops.size());
- CurDAG->UpdateNodeOperands(Load, TF, Load.getOperand(1), Load.getOperand(2));
- CurDAG->UpdateNodeOperands(Store, Load.getValue(1), Store.getOperand(1),
+ SDValue NewTF = CurDAG->UpdateNodeOperands(TF, &Ops[0], Ops.size());
+ SDValue NewLoad = CurDAG->UpdateNodeOperands(Load, NewTF,
+ Load.getOperand(1),
+ Load.getOperand(2));
+ CurDAG->UpdateNodeOperands(Store, NewLoad.getValue(1), Store.getOperand(1),
Store.getOperand(2), Store.getOperand(3));
}