C++ QualType::getCVRQualifiers方法代码示例

bool 
CXXConstructorDecl::isCopyConstructor(ASTContext &Context, 
                                      unsigned &TypeQuals) const {
  // C++ [class.copy]p2:
  //   A non-template constructor for class X is a copy constructor
  //   if its first parameter is of type X&, const X&, volatile X& or
  //   const volatile X&, and either there are no other parameters
  //   or else all other parameters have default arguments (8.3.6).
  if ((getNumParams() < 1) ||
      (getNumParams() > 1 && getParamDecl(1)->getDefaultArg() == 0))
    return false;

  const ParmVarDecl *Param = getParamDecl(0);

  // Do we have a reference type? Rvalue references don't count.
  const LValueReferenceType *ParamRefType =
    Param->getType()->getAsLValueReferenceType();
  if (!ParamRefType)
    return false;

  // Is it a reference to our class type?
  QualType PointeeType 
    = Context.getCanonicalType(ParamRefType->getPointeeType());
  QualType ClassTy 
    = Context.getTagDeclType(const_cast<CXXRecordDecl*>(getParent()));
  if (PointeeType.getUnqualifiedType() != ClassTy)
    return false;

  // We have a copy constructor.
  TypeQuals = PointeeType.getCVRQualifiers();
  return true;
}

DeclarationName 
DeclarationNameTable::getCXXSpecialName(DeclarationName::NameKind Kind, 
                                        QualType Ty) {
  assert(Kind >= DeclarationName::CXXConstructorName &&
         Kind <= DeclarationName::CXXConversionFunctionName &&
         "Kind must be a C++ special name kind");
  
  llvm::FoldingSet<CXXSpecialName> *SpecialNames 
    = static_cast<llvm::FoldingSet<CXXSpecialName>*>(CXXSpecialNamesImpl);

  DeclarationNameExtra::ExtraKind EKind;
  switch (Kind) {
  case DeclarationName::CXXConstructorName: 
    EKind = DeclarationNameExtra::CXXConstructor;
    assert(Ty.getCVRQualifiers() == 0 &&"Constructor type must be unqualified");
    break;
  case DeclarationName::CXXDestructorName:
    EKind = DeclarationNameExtra::CXXDestructor;
    assert(Ty.getCVRQualifiers() == 0 && "Destructor type must be unqualified");
    break;
  case DeclarationName::CXXConversionFunctionName:
    EKind = DeclarationNameExtra::CXXConversionFunction;
    break;
  default:
    return DeclarationName();
  }

  // Unique selector, to guarantee there is one per name.
  llvm::FoldingSetNodeID ID;
  ID.AddInteger(EKind);
  ID.AddPointer(Ty.getAsOpaquePtr());

  void *InsertPos = 0;
  if (CXXSpecialName *Name = SpecialNames->FindNodeOrInsertPos(ID, InsertPos))
    return DeclarationName(Name);

  CXXSpecialName *SpecialName = new CXXSpecialName;
  SpecialName->ExtraKindOrNumArgs = EKind;
  SpecialName->Type = Ty;
  SpecialName->FETokenInfo = 0;

  SpecialNames->InsertNode(SpecialName, InsertPos);
  return DeclarationName(SpecialName);
}

/// CastsAwayConstness - Check if the pointer conversion from SrcType to
/// DestType casts away constness as defined in C++ 5.2.11p8ff. This is used by
/// the cast checkers.  Both arguments must denote pointer (possibly to member)
/// types.
bool
CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType)
{
  // Casting away constness is defined in C++ 5.2.11p8 with reference to
  // C++ 4.4. We piggyback on Sema::IsQualificationConversion for this, since
  // the rules are non-trivial. So first we construct Tcv *...cv* as described
  // in C++ 5.2.11p8.
  assert((SrcType->isPointerType() || SrcType->isMemberPointerType()) &&
         "Source type is not pointer or pointer to member.");
  assert((DestType->isPointerType() || DestType->isMemberPointerType()) &&
         "Destination type is not pointer or pointer to member.");

  QualType UnwrappedSrcType = SrcType, UnwrappedDestType = DestType;
  llvm::SmallVector<unsigned, 8> cv1, cv2;

  // Find the qualifications.
  while (Self.UnwrapSimilarPointerTypes(UnwrappedSrcType, UnwrappedDestType)) {
    cv1.push_back(UnwrappedSrcType.getCVRQualifiers());
    cv2.push_back(UnwrappedDestType.getCVRQualifiers());
  }
  assert(cv1.size() > 0 && "Must have at least one pointer level.");

  // Construct void pointers with those qualifiers (in reverse order of
  // unwrapping, of course).
  QualType SrcConstruct = Self.Context.VoidTy;
  QualType DestConstruct = Self.Context.VoidTy;
  for (llvm::SmallVector<unsigned, 8>::reverse_iterator i1 = cv1.rbegin(),
                                                        i2 = cv2.rbegin();
       i1 != cv1.rend(); ++i1, ++i2)
  {
    SrcConstruct = Self.Context.getPointerType(
      SrcConstruct.getQualifiedType(*i1));
    DestConstruct = Self.Context.getPointerType(
      DestConstruct.getQualifiedType(*i2));
  }

  // Test if they're compatible.
  return SrcConstruct != DestConstruct &&
    !Self.IsQualificationConversion(SrcConstruct, DestConstruct);
}

/// getOrCreateType - Get the type from the cache or create a new
/// one if necessary.
llvm::DIType CGDebugInfo::getOrCreateType(QualType Ty,
                                          llvm::DICompileUnit Unit) {
  if (Ty.isNull())
    return llvm::DIType();
  
  // Check to see if the compile unit already has created this type.
  llvm::DIType &Slot = TypeCache[Ty.getAsOpaquePtr()];
  if (!Slot.isNull()) return Slot;

  // Handle CVR qualifiers, which recursively handles what they refer to.
  if (Ty.getCVRQualifiers())
    return Slot = CreateCVRType(Ty, Unit);

  // Work out details of type.
  switch (Ty->getTypeClass()) {
#define TYPE(Class, Base)
#define ABSTRACT_TYPE(Class, Base)
#define NON_CANONICAL_TYPE(Class, Base)
#define DEPENDENT_TYPE(Class, Base) case Type::Class:
#include "clang/AST/TypeNodes.def"
    assert(false && "Dependent types cannot show up in debug information");
    
  case Type::Complex:
  case Type::LValueReference:
  case Type::RValueReference:
  case Type::Vector:
  case Type::ExtVector:
  case Type::ExtQual:
  case Type::ObjCQualifiedInterface:
  case Type::ObjCQualifiedId:
  case Type::FixedWidthInt:
  case Type::BlockPointer:
  case Type::MemberPointer:
  case Type::TemplateSpecialization:
  case Type::QualifiedName:
  case Type::ObjCQualifiedClass:
    // Unsupported types
    return llvm::DIType();

  case Type::ObjCInterface: 
    Slot = CreateType(cast<ObjCInterfaceType>(Ty), Unit); break;
  case Type::Builtin: Slot = CreateType(cast<BuiltinType>(Ty), Unit); break;
  case Type::Pointer: Slot = CreateType(cast<PointerType>(Ty), Unit); break;
  case Type::Typedef: Slot = CreateType(cast<TypedefType>(Ty), Unit); break;
  case Type::Record:
  case Type::Enum:
    Slot = CreateType(cast<TagType>(Ty), Unit); 
    break;
  case Type::FunctionProto:
  case Type::FunctionNoProto:
    return Slot = CreateType(cast<FunctionType>(Ty), Unit);
    
  case Type::ConstantArray:
  case Type::VariableArray:
  case Type::IncompleteArray:
    return Slot = CreateType(cast<ArrayType>(Ty), Unit);
  case Type::TypeOfExpr:
    return Slot = getOrCreateType(cast<TypeOfExprType>(Ty)->getUnderlyingExpr()
                                  ->getType(), Unit);
  case Type::TypeOf:
    return Slot = getOrCreateType(cast<TypeOfType>(Ty)->getUnderlyingType(),
                                  Unit);
  }
  
  return Slot;
}