[llvm] [LV][EVL] Emit vp.merge intrinsic to enable out-loop reduction in EVL vectorization. (PR #101641)

[Mel Chen via llvm-commits]

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@@ -1486,6 +1486,17 @@ class LoopVectorizationCostModel {
     return InLoopReductions.contains(Phi);
   }
 
+  /// Returns true if the predicated reduction select should be used.
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Mel-Chen wrote:

Formatted and committed it, thanks.

https://github.com/llvm/llvm-project/pull/101641