[llvm] [RISCV] Lower PARTIAL_REDUCE_[S/U]MLA via zvqdotq (PR #140950)

[Luke Lau via llvm-commits]

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@@ -8364,6 +8376,27 @@ SDValue RISCVTargetLowering::lowerADJUST_TRAMPOLINE(SDValue Op,
   return Op.getOperand(0);
 }
 
+SDValue RISCVTargetLowering::lowerPARTIAL_REDUCE_MLA(SDValue Op,
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lukel97 wrote:

It looks like there's tablegen nodes defined for partial_reduce_{u,s}mla, could we mark the node as legal instead of custom and patterns in tablegen instead?

https://github.com/llvm/llvm-project/pull/140950