[llvm] [SelectionDAG][AArch64] Add dot product lowering in NEON for PARTIAL_REDUCE_*MLA ISD nodes (PR #140075)

[Sander de Smalen via llvm-commits]

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@@ -948,3 +1159,5 @@ end:
   %2 = add <4 x i32> %psum2, %psum1
   ret <4 x i32> %2
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK-I8MM: {{.*}}
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sdesmalen-arm wrote:

I think this shows regressions have been introduced when the code does not use the new lowering?

https://github.com/llvm/llvm-project/pull/140075