[llvm] [LV]Set tailfolding styles before computing feasible max VF. (PR #91403)

[via llvm-commits]

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@@ -1631,6 +1639,11 @@ class LoopVectorizationCostModel {
                                        ElementCount MaxSafeVF,
                                        bool FoldTailByMasking);
 
+  /// Checks if the scalable vectorization is supported and enabled. The result
+  /// is stored in \p IsScalableVectorizationAllowed and used later, if
+  /// requested.
+  bool isScalableVectorizationAllowed();
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ayalz wrote:

Not `const` because of debug dumps?

https://github.com/llvm/llvm-project/pull/91403