[llvm] [LV][EVL] Fix the check for legality of folding with EVL. (PR #125678)

[Luke Lau via llvm-commits]

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@@ -4109,7 +4110,8 @@ LoopVectorizationCostModel::computeMaxVF(ElementCount UserVF, unsigned UserIC) {
   // found modulo the vectorization factor is not zero, try to fold the tail
   // by masking.
   // FIXME: look for a smaller MaxVF that does divide TC rather than masking.
-  setTailFoldingStyles(MaxFactors.ScalableVF.isScalable(), UserIC);
+  bool ContainsScalableVF = MaxFactors.ScalableVF.isNonZero();
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lukel97 wrote:

Is `MaxFactors.ScalableVF.isScalable()` always true? We could make it an assert

https://github.com/llvm/llvm-project/pull/125678