[llvm] [BOLT][DWARF] Add support for cross-cu references for debug-names (PR #86015)

[Davide Italiano via llvm-commits]

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@@ -68,6 +68,16 @@ class DWARF5AcceleratorTable {
   std::unique_ptr<DebugBufferVector> releaseBuffer() {
     return std::move(FullTableBuffer);
   }
+  /// Adds a DIE that is referenced across CUs.
+  void addCrossCUDie(const DIE *Die) {
+    CrossCUDies.insert({Die->getOffset(), Die});
+  }
+  /// Returns true if the DIE can generate an entry for a cross cu reference.
+  /// This only checks TAGs of a DIE because when this is invoked DIE might not
+  /// be fully constructed.
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dcci wrote:

Do we have a case where the TAG of a DIE might not be enough to determinate whether we need to add the cross-TU DIE, or is this always safe?

https://github.com/llvm/llvm-project/pull/86015