[llvm] [LLVM][DWARF] Change .debug_names abbrev to be an index (PR #81200)

[David Blaikie via llvm-commits]

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@@ -360,6 +360,47 @@ class DWARF5AccelTable : public AccelTable<DWARF5AccelTableData> {
     unsigned Index;
     DWARF5AccelTableData::AttributeEncoding Encoding;
   };
+
+  struct AbbrevDescriptor {
+    uint32_t CompUnit : 1;
+    uint32_t TypeUnit : 1;
+    uint32_t DieOffset : 1;
+    uint32_t Parent : 2;
+    uint32_t TypeHash : 1;
+    uint32_t Tag : 26;
+  };
+  struct TagIndex {
+    uint32_t DieTag;
+    uint32_t Index;
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dwblaikie wrote:

Why does the index need to be keyed on both tag and index? The index is a unique identifier for an abbreviation (by definition).

https://github.com/llvm/llvm-project/pull/81200