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

[Felipe de Azevedo Piovezan via llvm-commits]

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@@ -1374,7 +1374,8 @@ void DWARFLinkerImpl::emitDWARFv5DebugNamesSection(const Triple &TargetTriple) {
       case DwarfUnit::AccelType::Namespace:
       case DwarfUnit::AccelType::Type: {
         DebugNames->addName(*DebugStrStrings.getExistingEntry(Info.String),
-                            Info.OutOffset, Info.Tag, CU->getUniqueID());
+                            Info.OutOffset, std::nullopt /*ParentDIEOffset*/,
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felipepiovezan wrote:

So this is what I was alluding to in the last paragraph of the commit message, it's not clear to me how/if the parallel linker has access to the parent DIE offset of the final, merged, debug information section. I was hoping to tackle this later

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