[llvm] [LV, VP]VP intrinsics support for the Loop Vectorizer + adding new tail-folding mode using EVL. (PR #76172)

[via llvm-commits]

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@@ -1521,6 +1525,36 @@ class LoopVectorizationCostModel {
     if (ForceTailFoldingStyle.getNumOccurrences()) {
       ChosenTailFoldingStyle.first = ChosenTailFoldingStyle.second =
           ForceTailFoldingStyle;
+      if (ChosenTailFoldingStyle.first == TailFoldingStyle::DataWithEVL) {
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ayalz wrote:

nit: it may be clearer to check `if (ForceTailFoldingStyle == TailFoldingStyle::DataWithEVL)`, otherwise one may wonder what about `second`, which in this case must be the same as `first`. I.e., the style one forces is applied regardless of whether IV can wrap or not.

https://github.com/llvm/llvm-project/pull/76172