[llvm] [SelectionDAG] Add support for the 3-way comparison intrinsics [US]CMP (PR #91871)

[Yingwei Zheng via llvm-commits]

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@@ -164,6 +164,12 @@ void DAGTypeLegalizer::ScalarizeVectorResult(SDNode *N, unsigned ResNo) {
   case ISD::ROTR:
     R = ScalarizeVecRes_BinOp(N);
     break;
+
+  case ISD::SCMP:
+  case ISD::UCMP:
+    R = ScalarizeVecRes_CMP(N);
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dtcxzyw wrote:

Missing test for scmp + scalarizevec

https://github.com/llvm/llvm-project/pull/91871