[llvm] [PatternMatch][VPlan] Add std::function match overload. NFCI (PR #146374)

[Nikita Popov via llvm-commits]

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@@ -50,6 +50,11 @@ template <typename Val, typename Pattern> bool match(Val *V, const Pattern &P) {
   return P.match(V);
 }
 
+template <typename Val = const Value, typename Pattern>
+std::function<bool(Val *)> match(const Pattern &P) {
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nikic wrote:

Needs to be implemented in a way that does not use std::function. You probably need to create a dedicated functor class for this.

I'm also not sure this should be just an overload of match(). Maybe something more explicit like match_fn()?

https://github.com/llvm/llvm-project/pull/146374