[llvm] Port Swift's merge function pass to llvm: merging functions that differ in constants (PR #68235)

[via llvm-commits]

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@@ -24,8 +24,13 @@ class Module;
 /// Merge functions that differ by constants.
 class MergeFuncIgnoringConstPass
     : public PassInfoMixin<MergeFuncIgnoringConstPass> {
+  bool ptrAuthEnabled = false;
+  unsigned ptrAuthKey = 0;
+  std::string mergeFuncSuffix = ".Tm";
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eeckstein wrote:

I think so. Thanks!

https://github.com/llvm/llvm-project/pull/68235