[llvm] [LV] Consider interleaving & tail-folding when -enable-wide-lane-mask=true (PR #163387)

[David Sherwood via llvm-commits]

================
@@ -209,9 +209,10 @@ struct TailFoldingInfo {
   TargetLibraryInfo *TLI;
   LoopVectorizationLegality *LVL;
   InterleavedAccessInfo *IAI;
+  bool UseWideLaneMask;
   TailFoldingInfo(TargetLibraryInfo *TLI, LoopVectorizationLegality *LVL,
-                  InterleavedAccessInfo *IAI)
-      : TLI(TLI), LVL(LVL), IAI(IAI) {}
+                  InterleavedAccessInfo *IAI, bool UseWideLaneMask = false)
----------------
david-arm wrote:

This flag is being set by a loop vectoriser flag called 'EnableWideLaneMask', which to me isn't the same as 'UseWideLaneMask'. The latter makes it sound like a decision has already been made, whereas the former sounds more like a possibility if the target wishes to use them.

https://github.com/llvm/llvm-project/pull/163387