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

[Kolya Panchenko 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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nikolaypanchenko wrote:

or `VPBuilder`, like there's `IRBuilder`

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