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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 *

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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

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#ifndef SHARE_OOPS_OOPSHIERARCHY_HPP

#define SHARE_OOPS_OOPSHIERARCHY_HPP

#include "metaprogramming/integralConstant.hpp"

#include "metaprogramming/primitiveConversions.hpp"

#include "utilities/globalDefinitions.hpp"

// OBJECT hierarchy

// This hierarchy is a representation hierarchy, i.e. if A is a superclass

// of B, A's representation is a prefix of B's representation.

typedef juint narrowOop; // Offset instead of address for an oop within a java object

// If compressed klass pointers then use narrowKlass.

typedef juint  narrowKlass;

typedef void* OopOrNarrowOopStar;

typedef class   markOopDesc*                markOop;

#ifndef CHECK_UNHANDLED_OOPS

typedef class oopDesc*                            oop;

typedef class   instanceOopDesc*            instanceOop;

typedef class   arrayOopDesc*                    arrayOop;

typedef class     objArrayOopDesc*            objArrayOop;

typedef class     typeArrayOopDesc*            typeArrayOop;

#else

// When CHECK_UNHANDLED_OOPS is defined, an "oop" is a class with a

// carefully chosen set of constructors and conversion operators to go

// to and from the underlying oopDesc pointer type.

//

// Because oop and its subclasses <type>Oop are class types, arbitrary

// conversions are not accepted by the compiler.  Applying a cast to

// an oop will cause the best matched conversion operator to be

// invoked returning the underlying oopDesc* type if appropriate.

// No copy constructors, explicit user conversions or operators of

// numerical type should be defined within the oop class. Most C++

// compilers will issue a compile time error concerning the overloading

// ambiguity between operators of numerical and pointer types. If

// a conversion to or from an oop to a numerical type is needed,

// use the inline template methods, cast_*_oop, defined below.

//

// Converting NULL to oop to Handle implicit is no longer accepted by the

// compiler because there are too many steps in the conversion.  Use Handle()

// instead, which generates less code anyway.

class Thread;

class PromotedObject;

class oopDesc;

extern bool CheckUnhandledOops;

class oop {

  oopDesc* _o;

  void register_oop();

  void unregister_oop();

  // friend class markOop;

public:

  void set_obj(const void* p)         {

    raw_set_obj(p);

    if (CheckUnhandledOops) register_oop();

  }

  void raw_set_obj(const void* p)     { _o = (oopDesc*)p; }

  oop()                               { set_obj(NULL); }

  oop(const oop& o)                   { set_obj(o.obj()); }

  oop(const volatile oop& o)          { set_obj(o.obj()); }

  oop(const void* p)                  { set_obj(p); }

  ~oop()                              {

    if (CheckUnhandledOops) unregister_oop();

  }

  oopDesc* obj()  const volatile      { return _o; }

  // General access

  oopDesc*  operator->() const        { return obj(); }

  bool operator==(const oop o) const;

  bool operator==(void *p) const      { return obj() == p; }

  bool operator!=(const volatile oop o) const;

  bool operator!=(void *p) const      { return obj() != p; }

  // Assignment

  oop& operator=(const oop& o)                            { _o = o.obj(); return *this; }

  volatile oop& operator=(const oop& o) volatile          { _o = o.obj(); return *this; }

  volatile oop& operator=(const volatile oop& o) volatile { _o = o.obj(); return *this; }

  // Explict user conversions

  operator void* () const             { return (void *)obj(); }

#ifndef SOLARIS

  operator void* () const volatile    { return (void *)obj(); }

#endif

  operator HeapWord* () const         { return (HeapWord*)obj(); }

  operator oopDesc* () const volatile { return obj(); }

  operator intptr_t* () const         { return (intptr_t*)obj(); }

  operator PromotedObject* () const   { return (PromotedObject*)obj(); }

  operator markOop () const volatile  { return markOop(obj()); }

  operator address   () const         { return (address)obj(); }

  // from javaCalls.cpp

  operator jobject () const           { return (jobject)obj(); }

  // from parNewGeneration and other things that want to get to the end of

  // an oop for stuff (like ObjArrayKlass.cpp)

  operator oop* () const              { return (oop *)obj(); }

};

template<>

struct PrimitiveConversions::Translate<oop> : public TrueType {

  typedef oop Value;

  typedef oopDesc* Decayed;

  static Decayed decay(Value x) { return x.obj(); }

  static Value recover(Decayed x) { return oop(x); }

};

#define DEF_OOP(type)                                                      \

   class type##OopDesc;                                                    \

   class type##Oop : public oop {                                          \

     public:                                                               \

       type##Oop() : oop() {}                                              \

       type##Oop(const oop& o) : oop(o) {}                                 \

       type##Oop(const volatile oop& o) : oop(o) {}                        \

       type##Oop(const void* p) : oop(p) {}                                \

       operator type##OopDesc* () const { return (type##OopDesc*)obj(); }  \

       type##OopDesc* operator->() const {                                 \

            return (type##OopDesc*)obj();                                  \

       }                                                                   \

       type##Oop& operator=(const type##Oop& o) {                          \

            oop::operator=(o);                                             \

            return *this;                                                  \

       }                                                                   \

       volatile type##Oop& operator=(const type##Oop& o) volatile {        \

            (void)const_cast<oop&>(oop::operator=(o));                     \

            return *this;                                                  \

       }                                                                   \

       volatile type##Oop& operator=(const volatile type##Oop& o) volatile {\

            (void)const_cast<oop&>(oop::operator=(o));                     \

            return *this;                                                  \

       }                                                                   \

   };                                                                      \

                                                                           \

   template<>                                                              \

   struct PrimitiveConversions::Translate<type##Oop> : public TrueType {   \

     typedef type##Oop Value;                                              \

     typedef type##OopDesc* Decayed;                                       \

                                                                           \

     static Decayed decay(Value x) { return (type##OopDesc*)x.obj(); }     \

     static Value recover(Decayed x) { return type##Oop(x); }              \

   };

DEF_OOP(instance);

DEF_OOP(array);

DEF_OOP(objArray);

DEF_OOP(typeArray);

#endif // CHECK_UNHANDLED_OOPS

// For CHECK_UNHANDLED_OOPS, it is ambiguous C++ behavior to have the oop

// structure contain explicit user defined conversions of both numerical

// and pointer type. Define inline methods to provide the numerical conversions.

template <class T> inline oop cast_to_oop(T value) {

  return (oop)(CHECK_UNHANDLED_OOPS_ONLY((void *))(value));

}

template <class T> inline T cast_from_oop(oop o) {

  return (T)(CHECK_UNHANDLED_OOPS_ONLY((void*))o);

}

inline bool check_obj_alignment(oop obj) {

  return (cast_from_oop<intptr_t>(obj) & MinObjAlignmentInBytesMask) == 0;

}

// The metadata hierarchy is separate from the oop hierarchy

//      class MetaspaceObj

class   ConstMethod;

class   ConstantPoolCache;

class   MethodData;

//      class Metadata

class   Method;

class   ConstantPool;

//      class CHeapObj

class   CompiledICHolder;

// The klass hierarchy is separate from the oop hierarchy.

class Klass;

class   InstanceKlass;

class     InstanceMirrorKlass;

class     InstanceClassLoaderKlass;

class     InstanceRefKlass;

class   ArrayKlass;

class     ObjArrayKlass;

class     TypeArrayKlass;

#endif // SHARE_OOPS_OOPSHIERARCHY_HPP