[llvm] [LV] Increase max VF if vectorized function variants exist (PR #66639)

[David Sherwood via llvm-commits]

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@@ -78,6 +78,11 @@ static cl::opt<LoopVectorizeHints::ScalableForceKind>
                 "Scalable vectorization is available and favored when the "
                 "cost is inconclusive.")));
 
+static cl::opt<bool> UseWiderVFIfVariantsPresent(
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david-arm wrote:

I feel like this option should really live in LoopVectorize.cpp since it's a cost model issue rather than a legality issue.

https://github.com/llvm/llvm-project/pull/66639