[llvm] [X86] Handle repeated blend mask in combineConcatVectorOps (PR #82155)

[via llvm-commits]

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@@ -55226,6 +55226,11 @@ static SDValue combineConcatVectorOps(const SDLoc &DL, MVT VT,
       if (NumOps == 2 && VT.is512BitVector() && Subtarget.useBWIRegs()) {
         uint64_t Mask0 = Ops[0].getConstantOperandVal(2);
         uint64_t Mask1 = Ops[1].getConstantOperandVal(2);
+        // MVT::v16i16 has repeated blend mask.
+        if (Op0.getSimpleValueType() == MVT::v16i16) {
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yubingex007-a11y wrote:

because v16i16 BLENDI's mask is i8 instead of i16

https://github.com/llvm/llvm-project/pull/82155