[llvm] [DWARFYAML] Implement debug_names support (PR #79666)

[James Henderson via llvm-commits]

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@@ -118,6 +118,28 @@ struct Unit {
   std::vector<Entry> Entries;
 };
 
+struct IdxForm {
+  llvm::dwarf::Index Idx;
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jh7370 wrote:

Nit: here and throughout this file, there's a lot of inconsistency about which namespace qualifiers to use (e.g. in just the `Unit` struct immediately above, the Format member has it, but the Type member doesn't!). It seems to me that all `llvm::` are redundant and should be deleted.

https://github.com/llvm/llvm-project/pull/79666