[lldb] DWZ 10/17: More support for .gnu_debugaltlink

[jankratochvil]

Summary

It was already added by D40468 but a few bits were still missing.

[jankratochvil]

My question about upstreaming of this patchset.

[jankratochvil]

I will be no longer involved with this patchset.

lldb/source/Plugins/SymbolFile/DWARF/DWARFContext.h

private:
   SectionData m_data_debug_loclists;
   SectionData m_data_debug_macro;
   SectionData m_data_debug_ranges;
   SectionData m_data_debug_rnglists;
   SectionData m_data_debug_str;
   SectionData m_data_debug_str_offsets;
   SectionData m_data_debug_tu_index;
   SectionData m_data_debug_types;
+  SectionData m_data_gnu_debug_alt_link;
 
   const DWARFDataExtractor &
   LoadOrGetSection(llvm::Optional<lldb::SectionType> main_section_type,
                    llvm::Optional<lldb::SectionType> dwo_section_type,
                    SectionData &data);
 
   const DWARFDataExtractor &getOrLoadCuIndexData();
   const DWARFDataExtractor &getOrLoadTuIndexData();
public:
   const DWARFDataExtractor &getOrLoadLocData();
   const DWARFDataExtractor &getOrLoadLocListsData();
   const DWARFDataExtractor &getOrLoadMacroData();
   const DWARFDataExtractor &getOrLoadRangesData();
   const DWARFDataExtractor &getOrLoadRngListsData();
   const DWARFDataExtractor &getOrLoadStrData();
   const DWARFDataExtractor &getOrLoadStrOffsetsData();
   const DWARFDataExtractor &getOrLoadDebugTypesData();
+  const DWARFDataExtractor &getOrLoadGNUDebugAltLink();
 
   bool isDwo() { return m_dwo_section_list != nullptr; }
 
   llvm::DWARFContext &GetAsLLVM();
 };
 } // namespace lldb_private
 
 #endif

lldb/source/Plugins/SymbolFile/DWARF/DWARFContext.cpp

return LoadOrGetSection(eSectionTypeDWARFDebugStrOffsets,
                           m_data_debug_str_offsets);
 }
 
 const DWARFDataExtractor &DWARFContext::getOrLoadDebugTypesData() {
   return LoadOrGetSection(eSectionTypeDWARFDebugTypes,
                           eSectionTypeDWARFDebugTypesDwo, m_data_debug_types);
 }
 
+const DWARFDataExtractor &DWARFContext::getOrLoadGNUDebugAltLink() {
+  return LoadOrGetSection(eSectionTypeDWARFGNUDebugAltLink, llvm::None,
+                          m_data_gnu_debug_alt_link);
+}
+
 llvm::DWARFContext &DWARFContext::GetAsLLVM() {
   if (!m_llvm_context) {
     llvm::StringMap<std::unique_ptr<llvm::MemoryBuffer>> section_map;
     uint8_t addr_size = 0;
     auto AddSection = [&](llvm::StringRef name, DWARFDataExtractor data) {
       // Set the address size the first time we see it.
       if (addr_size == 0)
         addr_size = data.GetAddressByteSize();