[llvm] [SelectionDAG] Add PARTIAL_REDUCE_U/SMLA ISD Nodes (PR #125207)

[Paul Walker via llvm-commits]

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@@ -3381,6 +3390,9 @@ bool DAGTypeLegalizer::SplitVectorOperand(SDNode *N, unsigned OpNo) {
   case ISD::EXPERIMENTAL_VECTOR_HISTOGRAM:
     Res = SplitVecOp_VECTOR_HISTOGRAM(N);
     break;
+  case ISD::PARTIAL_REDUCE_UMLA:
+  case ISD::PARTIAL_REDUCE_SMLA:
+    Res = SplitVecOp_PARTIAL_REDUCE_MLA(N);
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paulwalker-arm wrote:

As above, it's safer to add an explicit `break`.

https://github.com/llvm/llvm-project/pull/125207