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

[Nicholas Guy via llvm-commits]

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@@ -22,6 +22,26 @@ class LoopVectorizationLegality;
 class LoopVectorizationCostModel;
 class TargetLibraryInfo;
 struct HistogramInfo;
+class TargetTransformInfo;
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NickGuy-Arm wrote:

Very minor nit: Can we move this up one line, so it's grouped with the other `class` forward-declarations
```suggestion
class TargetLibraryInfo;
class TargetTransformInfo;
struct HistogramInfo;
```

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