[llvm] [BOLT][DWARF][NFC] Refactor address writers (PR #98094)

[Alexander Yermolovich via llvm-commits]

================
@@ -408,14 +430,16 @@ class DebugAddrWriter {
   }
 
   BinaryContext *BC;
-  /// Maps DWOID to AddressForDWOCU.
-  std::unordered_map<uint64_t, AddressForDWOCU> AddressMaps;
+  /// Address for the DWO CU associated with the address writer.
+  AddressForDWOCU Map;
+  uint8_t AddressByteSize;
+  std::optional<uint64_t> AddrOffsetSectionBase;
   /// Mutex used for parallel processing of debug info.
   std::mutex WriterMutex;
   std::unique_ptr<AddressSectionBuffer> Buffer;
   std::unique_ptr<raw_svector_ostream> AddressStream;
   /// Used to track sections that were not modified so that they can be re-used.
-  DenseMap<uint64_t, uint64_t> UnmodifiedAddressOffsets;
+  static DenseMap<uint64_t, uint64_t> UnmodifiedAddressOffsets;
----------------
ayermolo wrote:

For now it's fine, but for multi threaded step you will need to think of locks since this is shared between instances.

https://github.com/llvm/llvm-project/pull/98094