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

[Sander de Smalen via llvm-commits]

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@@ -21976,8 +21984,10 @@ static SDValue performIntrinsicCombine(SDNode *N,
       return Dot;
     if (SDValue WideAdd = tryLowerPartialReductionToWideAdd(N, Subtarget, DAG))
       return WideAdd;
-    return DAG.getPartialReduceAdd(SDLoc(N), N->getValueType(0),
-                                   N->getOperand(1), N->getOperand(2));
+    SDValue Input = N->getOperand(2);
+    return TargetLowering::getPartialReduceAdd(SDLoc(N), N->getValueType(0),
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sdesmalen-arm wrote:

Could this just call `expandPartialReduceMLA` instead?

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