[llvm] [LoopVectorizer] Add support for partial reductions (PR #92418)

[Graham Hunter via llvm-commits]

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@@ -27,6 +27,7 @@ struct VPWidenSelectRecipe;
 class VPReplicateRecipe;
 class VPRecipeBase;
 class VPlan;
+class VPPartialReductionRecipe;
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huntergr-arm wrote:

nit: Can be removed now.

https://github.com/llvm/llvm-project/pull/92418