Index: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
===================================================================
--- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -20588,7 +20588,8 @@
     EVT N0SrcSVT = N0Src.getValueType().getScalarType();
     EVT N1SrcSVT = N1Src.getValueType().getScalarType();
     if ((N0.isUndef() || N0SrcSVT == N1SrcSVT) &&
-        N0Src.getValueType().isVector() && N1Src.getValueType().isVector()) {
+        N0Src.getValueType().isFixedLengthVector() &&
+        N1Src.getValueType().isFixedLengthVector()) {
       EVT NewVT;
       SDLoc DL(N);
       SDValue NewIdx;