[llvm] [BOLT][DWARF] Refactor updateDWARFObjectAddressRanges (PR #96006)

[Amir Ayupov via llvm-commits]

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@@ -89,6 +89,13 @@ class DWARFRewriter {
   /// Store Rangelists writer for each DWO CU.
   RangeListsDWOWriers RangeListsWritersByCU;
 
+  using LegacyRangesDWOWriers =
+      std::unordered_map<uint64_t, std::unique_ptr<DebugRangesSectionWriter>>;
+  /// Store Ranges writer for each DWO CU.
+  LegacyRangesDWOWriers LegacyRangesWritersByCU;
+
+  std::unordered_map<uint64_t, DIE *> UpdatedDIEsByDWO;
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aaupov wrote:

Please add a brief comment about the purpose of the map.

https://github.com/llvm/llvm-project/pull/96006