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

[Paul Walker via llvm-commits]

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@@ -1245,6 +1245,11 @@ void SelectionDAGLegalize::LegalizeOp(SDNode *Node) {
         Node->getOpcode(),
         cast<MaskedHistogramSDNode>(Node)->getIndex().getValueType());
     break;
+  case ISD::PARTIAL_REDUCE_UMLA:
+  case ISD::PARTIAL_REDUCE_SMLA:
+    Action = TLI.getOperationAction(Node->getOpcode(),
+                                    Node->getOperand(0).getValueType());
+    break;
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paulwalker-arm wrote:

Is this necessary? I'd expect the default case to work fine for this node because the result and first operand's types must match?

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