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

[Philip Reames 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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preames wrote:

I briefly looked at doing this via tablegen, but decided to share the code with the reduce pattern matching.  Once I get hat migrated over to the partial_reduce_mla infrastructure, I may revisit the tablegen question.

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