[llvm] [LV] Vectorize histogram operations (PR #99851)

[Graham Hunter via llvm-commits]

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@@ -69,6 +69,7 @@ class LoopVectorizationCostModel;
 class LoopVersioning;
 
 struct VPCostContext;
+struct HistogramInfo;
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huntergr-arm wrote:

done

https://github.com/llvm/llvm-project/pull/99851