[llvm] [PatternMatch] Implement match_fn using bind_back (NFC) (PR #175811)

[Jakub Kuderski via llvm-commits]

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@@ -50,17 +50,11 @@ template <typename Val, typename Pattern> bool match(Val *V, const Pattern &P) {
   return P.match(V);
 }
 
-template <typename Val, typename Pattern> struct MatchFunctor {
-  const Pattern &P;
-  MatchFunctor(const Pattern &P) : P(P) {}
-  bool operator()(Val *V) const { return P.match(V); }
-};
-
 /// A match functor that can be used as a UnaryPredicate in functional
 /// algorithms like all_of.
 template <typename Val = const Value, typename Pattern>
-MatchFunctor<Val, Pattern> match_fn(const Pattern &P) {
-  return P;
+auto match_fn(const Pattern &P) {
+  return bind_back(match<Val, Pattern>, P);
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kuhar wrote:

You should be able to use `bind_back<match<Val, Pattern>>(P), no? Also elsewhere.

https://github.com/llvm/llvm-project/pull/175811