AVX512: combining setcc and zext is wrong on AVX512
because vector compare instruction puts result in mask register.
llvm-svn: 199798
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 8205fea..dd67b45 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5082,9 +5082,12 @@
if (N0.getOpcode() == ISD::SETCC) {
if (!LegalOperations && VT.isVector() &&
N0.getValueType().getVectorElementType() == MVT::i1) {
+ EVT N0VT = N0.getOperand(0).getValueType();
+ if (getSetCCResultType(N0VT) == N0.getValueType())
+ return SDValue();
+
// zext(setcc) -> (and (vsetcc), (1, 1, ...) for vectors.
// Only do this before legalize for now.
- EVT N0VT = N0.getOperand(0).getValueType();
EVT EltVT = VT.getVectorElementType();
SmallVector<SDValue,8> OneOps(VT.getVectorNumElements(),
DAG.getConstant(1, EltVT));