DAGCombiner: Don't fold xor into not if getNOT would introduce an illegal constant.
This happens e.g. with <2 x i64> -1 on x86_32. It cannot be generated directly
because i64 is illegal. It would be nice if getNOT would handle this
transparently, but I don't see a way to generate a legal constant there right
now. Fixes PR17487.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192795 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 8d6eab7..23e33d4 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -3583,7 +3583,7 @@
}
// fold (xor (and x, y), y) -> (and (not x), y)
if (N0.getOpcode() == ISD::AND && N0.getNode()->hasOneUse() &&
- N0->getOperand(1) == N1) {
+ N0->getOperand(1) == N1 && isTypeLegal(VT.getScalarType())) {
SDValue X = N0->getOperand(0);
SDValue NotX = DAG.getNOT(SDLoc(X), X, VT);
AddToWorkList(NotX.getNode());