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

[Florian Hahn via llvm-commits]

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@@ -63,6 +86,11 @@ class VPRecipeBuilder {
   /// created.
   SmallVector<VPHeaderPHIRecipe *, 4> PhisToFix;
 
+  /// The set of reduction exit instructions that will be scaled to
+  /// a smaller VF via partial reductions. paired with the scaling factor.
----------------
fhahn wrote:

```suggestion
  /// a smaller VF via partial reductions, paired with the scaling factor.
```

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