path: root/lib/AST/Type.cpp

//===--- Type.cpp - Type representation and manipulation ------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  This file implements type-related functionality.
//
//===----------------------------------------------------------------------===//

#include "clang/AST/ASTContext.h"
#include "clang/AST/Type.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/Expr.h"
#include "clang/AST/PrettyPrinter.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/raw_ostream.h"
using namespace clang;

bool QualType::isConstant(QualType T, ASTContext &Ctx) {
  if (T.isConstQualified())
    return true;

  if (const ArrayType *AT = Ctx.getAsArrayType(T))
    return AT->getElementType().isConstant(Ctx);

  return false;
}

void Type::Destroy(ASTContext& C) {
  this->~Type();
  C.Deallocate(this);
}

void VariableArrayType::Destroy(ASTContext& C) {
  if (SizeExpr)
    SizeExpr->Destroy(C);
  this->~VariableArrayType();
  C.Deallocate(this);
}

void DependentSizedArrayType::Destroy(ASTContext& C) {
  // FIXME: Resource contention like in ConstantArrayWithExprType ?
  // May crash, depending on platform or a particular build.
  // SizeExpr->Destroy(C);
  this->~DependentSizedArrayType();
  C.Deallocate(this);
}

void DependentSizedArrayType::Profile(llvm::FoldingSetNodeID &ID,
                                      ASTContext &Context,
                                      QualType ET,
                                      ArraySizeModifier SizeMod,
                                      unsigned TypeQuals,
                                      Expr *E) {
  ID.AddPointer(ET.getAsOpaquePtr());
  ID.AddInteger(SizeMod);
  ID.AddInteger(TypeQuals);
  E->Profile(ID, Context, true);
}

void
DependentSizedExtVectorType::Profile(llvm::FoldingSetNodeID &ID,
                                     ASTContext &Context,
                                     QualType ElementType, Expr *SizeExpr) {
  ID.AddPointer(ElementType.getAsOpaquePtr());
  SizeExpr->Profile(ID, Context, true);
}

void DependentSizedExtVectorType::Destroy(ASTContext& C) {
  // FIXME: Deallocate size expression, once we're cloning properly.
//  if (SizeExpr)
//    SizeExpr->Destroy(C);
  this->~DependentSizedExtVectorType();
  C.Deallocate(this);
}

/// getArrayElementTypeNoTypeQual - If this is an array type, return the
/// element type of the array, potentially with type qualifiers missing.
/// This method should never be used when type qualifiers are meaningful.
const Type *Type::getArrayElementTypeNoTypeQual() const {
  // If this is directly an array type, return it.
  if (const ArrayType *ATy = dyn_cast<ArrayType>(this))
    return ATy->getElementType().getTypePtr();

  // If the canonical form of this type isn't the right kind, reject it.
  if (!isa<ArrayType>(CanonicalType))
    return 0;

  // If this is a typedef for an array type, strip the typedef off without
  // losing all typedef information.
  return cast<ArrayType>(getUnqualifiedDesugaredType())
    ->getElementType().getTypePtr();
}

/// \brief Retrieve the unqualified variant of the given type, removing as
/// little sugar as possible.
///
/// This routine looks through various kinds of sugar to find the 
/// least-desuraged type that is unqualified. For example, given:
///
/// \code
/// typedef int Integer;
/// typedef const Integer CInteger;
/// typedef CInteger DifferenceType;
/// \endcode
///
/// Executing \c getUnqualifiedTypeSlow() on the type \c DifferenceType will
/// desugar until we hit the type \c Integer, which has no qualifiers on it.
QualType QualType::getUnqualifiedTypeSlow() const {
  QualType Cur = *this;
  while (true) {
    if (!Cur.hasQualifiers())
      return Cur;
    
    const Type *CurTy = Cur.getTypePtr();
    switch (CurTy->getTypeClass()) {
#define ABSTRACT_TYPE(Class, Parent)
#define TYPE(Class, Parent)                                  \
    case Type::Class: {                                      \
      const Class##Type *Ty = cast<Class##Type>(CurTy);      \
      if (!Ty->isSugared())                                  \
        return Cur.getLocalUnqualifiedType();                \
      Cur = Ty->desugar();                                   \
      break;                                                 \
    }
#include "clang/AST/TypeNodes.def"
    }
  }
  
  return Cur.