[llvm] [PatternMatching] Add generic API for matching constants using custom conditions (PR #85676)

[Yingwei Zheng via llvm-commits]

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@@ -452,30 +470,93 @@ template <typename Predicate> struct apf_pred_ty : public Predicate {
 //
 ///////////////////////////////////////////////////////////////////////////////
 
+template <typename APTy> struct custom_checkfn {
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dtcxzyw wrote:

It would be better to add some unit tests for new helpers.


https://github.com/llvm/llvm-project/pull/85676