[X86] Fix lowering to illegal type in LowerINSERT_VECTOR_ELT

Differential Revision: https://reviews.llvm.org/D106780

Author: xiangzh1

llvm/lib/Target/X86/X86ISelLowering.cpp

@@ -18970,6 +18970,9 @@ SDValue X86TargetLowering::LowerINSERT_VECTOR_ELT(SDValue Op,
 
     MVT IdxSVT = MVT::getIntegerVT(EltSizeInBits);
     MVT IdxVT = MVT::getVectorVT(IdxSVT, NumElts);
+    if (!isTypeLegal(IdxSVT) || !isTypeLegal(IdxVT))
+      return SDValue();
+
     SDValue IdxExt = DAG.getZExtOrTrunc(N2, dl, IdxSVT);
     SDValue IdxSplat = DAG.getSplatBuildVector(IdxVT, dl, IdxExt);
     SDValue EltSplat = DAG.getSplatBuildVector(VT, dl, N1);