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

[Alexey Bataev via llvm-commits]

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@@ -1633,6 +1634,23 @@ class LoopVectorizationCostModel {
     return foldTailByMasking() || Legal->blockNeedsPredication(BB);
   }
 
+  /// Returns true if VP intrinsics with explicit vector length support should
+  /// be generated in the tail folded loop.
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alexey-bataev wrote:

Reowked it, now it just checks if getTailFoldingStyle() == TailFoldingStyle::DataWithEVL

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