[llvm] [VPlan] Implement VPExtendedReduction, VPMulAccumulateReductionRecipe and corresponding vplan transformations. (PR #137746)

[Florian Hahn via llvm-commits]

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@@ -273,6 +273,8 @@ Type *VPTypeAnalysis::inferScalarType(const VPValue *V) {
             // TODO: Use info from interleave group.
             return V->getUnderlyingValue()->getType();
           })
+          .Case<VPExtendedReductionRecipe, VPMulAccumulateReductionRecipe>(
+              [](const auto *R) { return R->getResultType(); })
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fhahn wrote:

Yep meant `VPMulAccumulateReductionRecipe`. Setting the result type only in some cases seems confusing. Could we set it unconditionally to `RecurrenceDescriptor::getRecurrenceType`?

https://github.com/llvm/llvm-project/pull/137746