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

[Florian Hahn via llvm-commits]

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@@ -331,6 +344,8 @@ class LoopVectorizationPlanner {
   /// Profitable vector factors.
   SmallVector<VectorizationFactor, 8> ProfitableVFs;
 
+  SmallVector<PartialReductionChain> PartialReductionChains;
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fhahn wrote:

Is this needed in the scope of LVP or can be limited to constructing the VPlans?

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