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

[Alexander Yermolovich via llvm-commits]

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@@ -360,6 +360,49 @@ class DWARF5AccelTable : public AccelTable<DWARF5AccelTableData> {
     unsigned Index;
     DWARF5AccelTableData::AttributeEncoding Encoding;
   };
+  union AbbrevDescriptor {
+    struct {
+      uint32_t CompUnit : 1;
+      uint32_t TypeUnit : 1;
+      uint32_t DieOffset : 1;
+      uint32_t Parent : 2;
+      uint32_t TypeHash : 1;
+      uint32_t Tag : 26;
+    } Bits;
+    uint32_t Value = 0;
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ayermolo wrote:

Changed it struct. Although it requires bit_cast and memset. Unless there is some c++ I am not aware of. 

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