[llvm] [LV][EVL] Support in-loop reduction using tail folding with EVL. (PR #90184)

[Mel Chen via llvm-commits]

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@@ -57,6 +58,11 @@ class VectorBuilder {
     return RetType();
   }
 
+  // Helper function for creating VP intrinsic call.
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Mel-Chen wrote:

Indeed, this can be adjusted later. (But I would prefer a shorter name, perhaps just VectorPredBuilder would be good enough?)

https://github.com/llvm/llvm-project/pull/90184