[clang] [llvm] Reland "[DebugMetadata][DwarfDebug] Support function-local types in lexical block scopes (4/7)" (PR #165032)

[David Blaikie via cfe-commits]

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@@ -538,55 +546,71 @@ class MetadataLoader::MetadataLoaderImpl {
 
   /// Move local imports from DICompileUnit's 'imports' field to
   /// DISubprogram's retainedNodes.
+  /// Move function-local enums from DICompileUnit's enums
+  /// to DISubprogram's retainedNodes.
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dwblaikie wrote:

I think the functional change of moving function-local enums from the CU to the Subprogram seems like it could be a distinct change? It has observable effects (so it's not NFC) but they can be implemented/tested separately from the rest of this work.

Maybe worth discussing the tradeoffs of that change too (like what happens if that function-local enum is referenced from somewhere else, like a template instantiation but then the original function is optimized away (not sure if we could quite get the stars to align with all those things, but maybe)) - but I feel this has all drawn out far enough so if you just want to go ahead with this, you could separate out that work without it being in a separate patch/review/etc.



https://github.com/llvm/llvm-project/pull/165032