[llvm] [BOLT][DWARF] Refactor legacy ranges writers (PR #96006)

[Alexander Yermolovich via llvm-commits]

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@@ -232,6 +238,9 @@ class DebugRangesSectionWriter {
   static constexpr uint64_t EmptyRangesOffset{0};
 
 private:
+  /// Stores DIE to be updated for CU.
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ayermolo wrote:

Change to Unit/Type DIE

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