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* version 2 for more details (a copy is included in the LICENSE file that
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* 2 along with this work; if not, write to the Free Software Foundation,
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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;
#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 "C" bool CheckUnhandledOops;
class oop {
oopDesc* _o;
void register_oop();
void unregister_oop();
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 { return obj() == o.obj(); }
bool operator==(void *p) const { return obj() == p; }
bool operator!=(const volatile oop o) const { return obj() != o.obj(); }
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 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);
}
// 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