C++ DICompositeType::isForwardDecl方法代码示例

DITypeIdentifierMap
llvm::generateDITypeIdentifierMap(const NamedMDNode *CU_Nodes) {
  DITypeIdentifierMap Map;
  for (unsigned CUi = 0, CUe = CU_Nodes->getNumOperands(); CUi != CUe; ++CUi) {
    DICompileUnit CU = cast<MDCompileUnit>(CU_Nodes->getOperand(CUi));
    DIArray Retain = CU.getRetainedTypes();
    for (unsigned Ti = 0, Te = Retain.size(); Ti != Te; ++Ti) {
      if (!isa<MDCompositeType>(Retain[Ti]))
        continue;
      DICompositeType Ty = cast<MDCompositeType>(Retain[Ti]);
      if (MDString *TypeId = Ty.getIdentifier()) {
        // Definition has priority over declaration.
        // Try to insert (TypeId, Ty) to Map.
        std::pair<DITypeIdentifierMap::iterator, bool> P =
            Map.insert(std::make_pair(TypeId, Ty));
        // If TypeId already exists in Map and this is a definition, replace
        // whatever we had (declaration or definition) with the definition.
        if (!P.second && !Ty.isForwardDecl())
          P.first->second = Ty;
      }
    }
  }
  return Map;
}

//.........这里部分代码省略.........
    break;
  case dwarf::DW_TAG_structure_type:
  case dwarf::DW_TAG_union_type:
  case dwarf::DW_TAG_class_type: {
    // Add elements to structure type.
    DIArray Elements = CTy.getTypeArray();

    // A forward struct declared type may not have elements available.
    unsigned N = Elements.getNumElements();
    if (N == 0)
      break;

    // Add elements to structure type.
    for (unsigned i = 0; i < N; ++i) {
      DIDescriptor Element = Elements.getElement(i);
      DIE *ElemDie = NULL;
      if (Element.isSubprogram()) {
        DISubprogram SP(Element);
        ElemDie = DD->createSubprogramDIE(DISubprogram(Element));
        if (SP.isProtected())
          addUInt(ElemDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_flag,
                  dwarf::DW_ACCESS_protected);
        else if (SP.isPrivate())
          addUInt(ElemDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_flag,
                  dwarf::DW_ACCESS_private);
        else 
          addUInt(ElemDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_flag,
            dwarf::DW_ACCESS_public);
        if (SP.isExplicit())
          addUInt(ElemDie, dwarf::DW_AT_explicit, dwarf::DW_FORM_flag, 1);
      }
      else if (Element.isVariable()) {
        DIVariable DV(Element);
        ElemDie = new DIE(dwarf::DW_TAG_variable);
        addString(ElemDie, dwarf::DW_AT_name, dwarf::DW_FORM_string,
                  DV.getName());
        addType(ElemDie, DV.getType());
        addUInt(ElemDie, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
        addUInt(ElemDie, dwarf::DW_AT_external, dwarf::DW_FORM_flag, 1);
        addSourceLine(ElemDie, DV);
      } else if (Element.isDerivedType())
        ElemDie = createMemberDIE(DIDerivedType(Element));
      else
        continue;
      Buffer.addChild(ElemDie);
    }

    if (CTy.isAppleBlockExtension())
      addUInt(&Buffer, dwarf::DW_AT_APPLE_block, dwarf::DW_FORM_flag, 1);

    unsigned RLang = CTy.getRunTimeLang();
    if (RLang)
      addUInt(&Buffer, dwarf::DW_AT_APPLE_runtime_class,
              dwarf::DW_FORM_data1, RLang);

    DICompositeType ContainingType = CTy.getContainingType();
    if (DIDescriptor(ContainingType).isCompositeType())
      addDIEEntry(&Buffer, dwarf::DW_AT_containing_type, dwarf::DW_FORM_ref4,
                  getOrCreateTypeDIE(DIType(ContainingType)));
    else {
      DIDescriptor Context = CTy.getContext();
      addToContextOwner(&Buffer, Context);
    }

    if (CTy.isObjcClassComplete())
      addUInt(&Buffer, dwarf::DW_AT_APPLE_objc_complete_type,
              dwarf::DW_FORM_flag, 1);

    if (Tag == dwarf::DW_TAG_class_type) 
      addTemplateParams(Buffer, CTy.getTemplateParams());

    break;
  }
  default:
    break;
  }

  // Add name if not anonymous or intermediate type.
  if (!Name.empty())
    addString(&Buffer, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);

  if (Tag == dwarf::DW_TAG_enumeration_type || Tag == dwarf::DW_TAG_class_type
      || Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type)
    {
    // Add size if non-zero (derived types might be zero-sized.)
    if (Size)
      addUInt(&Buffer, dwarf::DW_AT_byte_size, 0, Size);
    else {
      // Add zero size if it is not a forward declaration.
      if (CTy.isForwardDecl())
        addUInt(&Buffer, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
      else
        addUInt(&Buffer, dwarf::DW_AT_byte_size, 0, 0);
    }

    // Add source line info if available.
    if (!CTy.isForwardDecl())
      addSourceLine(&Buffer, CTy);
  }
}