[llvm] [AsmPrinter][DebugNames] Implement DW_IDX_parent entries (PR #77457)

[Adrian Prantl via llvm-commits]

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@@ -496,15 +549,32 @@ void Dwarf5AccelTableWriter::emitAbbrevs() const {
 }
 
 void Dwarf5AccelTableWriter::emitEntry(
-    const DWARF5AccelTableData &Entry) const {
+    const DWARF5AccelTableData &Entry,
+    const DenseMap<uint64_t, MCSymbol *> &DIEOffsetToAccelEntryLabel,
+    DenseSet<MCSymbol *> &EmittedAccelEntrySymbols) const {
   std::optional<DWARF5AccelTable::UnitIndexAndEncoding> EntryRet =
       getIndexForEntry(Entry);
-  uint32_t AbbrvTag = constructAbbreviationTag(Entry.getDieTag(), EntryRet);
+  std::optional<uint64_t> MaybeParentOffset = Entry.getParentDieOffset();
+  std::optional<dwarf::Form> MaybeParentForm =
+      getFormForIdxParent(IndexedOffsets, MaybeParentOffset);
+  uint32_t AbbrvTag =
+      constructAbbreviationTag(Entry.getDieTag(), EntryRet, MaybeParentForm);
   auto AbbrevIt = Abbreviations.find(AbbrvTag);
   assert(AbbrevIt != Abbreviations.end() &&
          "Why wasn't this abbrev generated?");
   assert(getTagFromAbbreviationTag(AbbrevIt->first) == Entry.getDieTag() &&
          "Invalid Tag");
+
+  auto EntrySymbolIt = DIEOffsetToAccelEntryLabel.find(Entry.getDieOffset());
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adrian-prantl wrote:

Though IIUC, in AsmPrinter you'd have at most one .o and one .dwo file, so you may be able to get away with having just one extra bit for the disambiguation.

https://github.com/llvm/llvm-project/pull/77457