[llvm] [AArch64][NEON] Lower fixed-width add partial reductions to dot product (PR #107078)

[Sam Tebbs via llvm-commits]

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@@ -21781,7 +21782,12 @@ SDValue tryLowerPartialReductionToDot(SDNode *N,
              Intrinsic::experimental_vector_partial_reduce_add &&
          "Expected a partial reduction node");
 
-  if (!Subtarget->isSVEorStreamingSVEAvailable())
+  if (!Subtarget->isSVEorStreamingSVEAvailable() &&
+      !Subtarget->isNeonAvailable())
+    return SDValue();
+
+  // Fixed-width requires the dotprod feature, both for Neon and SVE
+  if (!N->getValueType(0).isScalableVT() && !Subtarget->hasDotProd())
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SamTebbs33 wrote:

Done.

https://github.com/llvm/llvm-project/pull/107078