[nfc] [lldb] DWZ 08/17: Use DIERef for DIEToClangType m_forward_decl_die_to_clang_type and GetForwardDeclDieToClangType()

[jankratochvil]

Summary

After D96236 using just DWARFDebugInfoEntry * is ambiguous as it does not contain MainCU. DIERef (after D96239) does contain it and it has the same sizeof as DWARFDebugInfoEntry *. This replacement should have no real performance disadvantage.

My question about upstreaming of this patchset.

[jankratochvil]

I will be no longer involved with this patchset.

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

if (attrs.is_forward_declaration) {
     }
   }
   DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
                DW_TAG_value_to_name(tag), type_name_cstr);
 
   CompilerType enumerator_clang_type;
   CompilerType clang_type;
   clang_type.SetCompilerType(
-      &m_ast, dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
+      &m_ast,
+      dwarf->GetForwardDeclDIERefToClangType().lookup(*die.GetDIERef()));
   if (!clang_type) {
     if (attrs.type.IsValid()) {
       Type *enumerator_type =
           dwarf->ResolveTypeUID(attrs.type.Reference(), true);
       if (enumerator_type)
         enumerator_clang_type = enumerator_type->GetFullCompilerType();
     }
 
if (type_sp) {
         LinkDeclContextToDIE(defn_decl_ctx, die);
       return type_sp;
     }
   }
   assert(tag_decl_kind != -1);
   (void)tag_decl_kind;
   bool clang_type_was_created = false;
   clang_type.SetCompilerType(
-      &m_ast, dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
+      &m_ast,
+      dwarf->GetForwardDeclDIERefToClangType().lookup(*die.GetDIERef()));
   if (!clang_type) {
     clang::DeclContext *decl_ctx =
         GetClangDeclContextContainingDIE(die, nullptr);
 
     PrepareContextToReceiveMembers(m_ast, GetClangASTImporter(), decl_ctx, die,
                                    attrs.name.GetCString());
 
     if (attrs.accessibility == eAccessNone && decl_ctx) {
if (!die.HasChildren()) {
       // needs to be defined.
       assert(!dwarf->GetForwardDeclClangTypeToDie().count(
                  ClangUtil::RemoveFastQualifiers(clang_type)
                      .GetOpaqueQualType()) &&
              "Type already in the forward declaration map!");
       // Can't assume m_ast.GetSymbolFile() is actually a
       // SymbolFileDWARF, it can be a SymbolFileDWARFDebugMap for Apple
       // binaries.
-      dwarf->GetForwardDeclDieToClangType()[die.GetDIE()] =
+      dwarf->GetForwardDeclDIERefToClangType()[*die.GetDIERef()] =
           clang_type.GetOpaqueQualType();
       dwarf->GetForwardDeclClangTypeToDie().try_emplace(
           ClangUtil::RemoveFastQualifiers(clang_type).GetOpaqueQualType(),
           *die.GetDIERef());
       m_ast.SetHasExternalStorage(clang_type.GetOpaqueQualType(), true);
     }
   }
 

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

public:
 
   static lldb::LanguageType GetLanguage(DWARFUnit &unit);
   /// Same as GetLanguage() but reports all C++ versions as C++ (no version).
   static lldb::LanguageType GetLanguageFamily(DWARFUnit &unit);
 
 protected:
   typedef llvm::DenseMap<DIERef, lldb_private::Type *> DIERefToTypePtr;
   typedef llvm::DenseMap<DIERef, lldb::VariableSP> DIERefToVariableSP;
-  typedef llvm::DenseMap<const DWARFDebugInfoEntry *,
-                         lldb::opaque_compiler_type_t>
-      DIEToClangType;
+  typedef llvm::DenseMap<DIERef, lldb::opaque_compiler_type_t>
+      DIERefToClangType;
   typedef llvm::DenseMap<lldb::opaque_compiler_type_t, DIERef> ClangTypeToDIE;
 
   SymbolFileDWARF(const SymbolFileDWARF &) = delete;
   const SymbolFileDWARF &operator=(const SymbolFileDWARF &) = delete;
 
   virtual void LoadSectionData(lldb::SectionType sect_type,
                                lldb_private::DWARFDataExtractor &data);
 
protected:
   void UpdateExternalModuleListIfNeeded();
 
   virtual DIERefToTypePtr &GetDIERefToType() { return m_dieref_to_type; }
 
   virtual DIERefToVariableSP &GetDIERefToVariable() {
     return m_dieref_to_variable_sp;
   }
 
-  virtual DIEToClangType &GetForwardDeclDieToClangType() {
-    return m_forward_decl_die_to_clang_type;
+  virtual DIERefToClangType &GetForwardDeclDIERefToClangType() {
+    return m_forward_decl_dieref_to_clang_type;
   }
 
   virtual ClangTypeToDIE &GetForwardDeclClangTypeToDie() {
     return m_forward_decl_clang_type_to_die;
   }
 
   void BuildCuTranslationTable();
   llvm::Optional<uint32_t> GetDWARFUnitIndex(uint32_t cu_idx);
protected:
 
   typedef std::set<DIERef> DIERefSet;
   typedef llvm::StringMap<DIERefSet> NameToOffsetMap;
   NameToOffsetMap m_function_scope_qualified_name_map;
   std::unique_ptr<DWARFDebugRanges> m_ranges;
   UniqueDWARFASTTypeMap m_unique_ast_type_map;
   DIERefToTypePtr m_dieref_to_type;
   DIERefToVariableSP m_dieref_to_variable_sp;
-  DIEToClangType m_forward_decl_die_to_clang_type;
+  DIERefToClangType m_forward_decl_dieref_to_clang_type;
   ClangTypeToDIE m_forward_decl_clang_type_to_die;
   llvm::DenseMap<dw_offset_t, lldb_private::FileSpecList>
       m_type_unit_support_files;
   std::vector<uint32_t> m_lldb_cu_to_dwarf_unit;
 };
 
 #endif // LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_SYMBOLFILEDWARF_H

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

public:
 
   llvm::Optional<uint32_t> GetDwoNum() override { return GetID() >> 32; }
 
 protected:
   DIERefToTypePtr &GetDIERefToType() override;
 
   DIERefToVariableSP &GetDIERefToVariable() override;
 
-  DIEToClangType &GetForwardDeclDieToClangType() override;
+  DIERefToClangType &GetForwardDeclDIERefToClangType() override;
 
   ClangTypeToDIE &GetForwardDeclClangTypeToDie() override;
 
   UniqueDWARFASTTypeMap &GetUniqueDWARFASTTypeMap() override;
 
   lldb::TypeSP FindDefinitionTypeForDWARFDeclContext(
       const DWARFDeclContext &die_decl_ctx) override;
 

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

 SymbolFileDWARF::DIERefToTypePtr &SymbolFileDWARFDwo::GetDIERefToType() {
   return GetBaseSymbolFile().GetDIERefToType();
 }
 
 SymbolFileDWARF::DIERefToVariableSP &SymbolFileDWARFDwo::GetDIERefToVariable() {
   return GetBaseSymbolFile().GetDIERefToVariable();
 }
 
-SymbolFileDWARF::DIEToClangType &
-SymbolFileDWARFDwo::GetForwardDeclDieToClangType() {
-  return GetBaseSymbolFile().GetForwardDeclDieToClangType();
+SymbolFileDWARF::DIERefToClangType &
+SymbolFileDWARFDwo::GetForwardDeclDIERefToClangType() {
+  return GetBaseSymbolFile().GetForwardDeclDIERefToClangType();
 }
 
 SymbolFileDWARF::ClangTypeToDIE &
 SymbolFileDWARFDwo::GetForwardDeclClangTypeToDie() {
   return GetBaseSymbolFile().GetForwardDeclClangTypeToDie();
 }
 
 void SymbolFileDWARFDwo::GetObjCMethods(