[llvm] [Utils] Identity map module-level debug info on first use in CloneFunction* (PR #118627)

[Artem Pianykh via llvm-commits]

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@@ -322,16 +317,21 @@ void llvm::CloneFunctionInto(Function *NewFunc, const Function *OldFunc,
   DISubprogram *SPClonedWithinModule =
       CollectDebugInfoForCloning(*OldFunc, Changes, DIFinder);
 
-  ModuleLevelChanges =
-      BuildDebugInfoMDMap(VMap.MD(), Changes, DIFinder, SPClonedWithinModule);
+  MetadataSetTy IdentityMD;
+  FindDebugInfoToIdentityMap(IdentityMD, Changes, DIFinder,
+                             SPClonedWithinModule);
 
-  const auto RemapFlag = ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges;
+  // Current implementation always upgrades from local changes to module level
+  // changes due to the way metadata cloning is done. See
+  // BuildDebugInfoToIdentityMap for more details.
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artempyanykh wrote:

> I can't find `BuildDebugInfoToIdentityMap` in this patch

Yes, sorry, this was renamed to `FindDebugInfoToIdentityMap`.

--

Updated the comment with the suggestion.

https://github.com/llvm/llvm-project/pull/118627