Java example source code file (oop.inline.hpp)
The oop.inline.hpp Java example source code/*
* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* 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.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#ifndef SHARE_VM_OOPS_OOP_INLINE_HPP
#define SHARE_VM_OOPS_OOP_INLINE_HPP
#include "gc_implementation/shared/ageTable.hpp"
#include "gc_implementation/shared/markSweep.inline.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "memory/barrierSet.inline.hpp"
#include "memory/cardTableModRefBS.hpp"
#include "memory/genCollectedHeap.hpp"
#include "memory/generation.hpp"
#include "memory/specialized_oop_closures.hpp"
#include "oops/arrayKlass.hpp"
#include "oops/arrayOop.hpp"
#include "oops/klass.inline.hpp"
#include "oops/markOop.inline.hpp"
#include "oops/oop.hpp"
#include "runtime/atomic.hpp"
#include "runtime/os.hpp"
#include "utilities/macros.hpp"
#ifdef TARGET_ARCH_x86
# include "bytes_x86.hpp"
#endif
#ifdef TARGET_ARCH_sparc
# include "bytes_sparc.hpp"
#endif
#ifdef TARGET_ARCH_zero
# include "bytes_zero.hpp"
#endif
#ifdef TARGET_ARCH_arm
# include "bytes_arm.hpp"
#endif
#ifdef TARGET_ARCH_ppc
# include "bytes_ppc.hpp"
#endif
// Implementation of all inlined member functions defined in oop.hpp
// We need a separate file to avoid circular references
inline void oopDesc::release_set_mark(markOop m) {
OrderAccess::release_store_ptr(&_mark, m);
}
inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
}
inline Klass* oopDesc::klass() const {
if (UseCompressedClassPointers) {
return Klass::decode_klass_not_null(_metadata._compressed_klass);
} else {
return _metadata._klass;
}
}
inline Klass* oopDesc::klass_or_null() const volatile {
// can be NULL in CMS
if (UseCompressedClassPointers) {
return Klass::decode_klass(_metadata._compressed_klass);
} else {
return _metadata._klass;
}
}
inline int oopDesc::klass_gap_offset_in_bytes() {
assert(UseCompressedClassPointers, "only applicable to compressed klass pointers");
return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass);
}
inline Klass** oopDesc::klass_addr() {
// Only used internally and with CMS and will not work with
// UseCompressedOops
assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
return (Klass**) &_metadata._klass;
}
inline narrowKlass* oopDesc::compressed_klass_addr() {
assert(UseCompressedClassPointers, "only called by compressed klass pointers");
return &_metadata._compressed_klass;
}
inline void oopDesc::set_klass(Klass* k) {
// since klasses are promoted no store check is needed
assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*");
assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*");
if (UseCompressedClassPointers) {
*compressed_klass_addr() = Klass::encode_klass_not_null(k);
} else {
*klass_addr() = k;
}
}
inline int oopDesc::klass_gap() const {
return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
}
inline void oopDesc::set_klass_gap(int v) {
if (UseCompressedClassPointers) {
*(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
}
}
inline void oopDesc::set_klass_to_list_ptr(oop k) {
// This is only to be used during GC, for from-space objects, so no
// barrier is needed.
if (UseCompressedClassPointers) {
_metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling)
} else {
_metadata._klass = (Klass*)(address)k;
}
}
inline oop oopDesc::list_ptr_from_klass() {
// This is only to be used during GC, for from-space objects.
if (UseCompressedClassPointers) {
return decode_heap_oop((narrowOop)_metadata._compressed_klass);
} else {
// Special case for GC
return (oop)(address)_metadata._klass;
}
}
inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); }
inline bool oopDesc::is_a(Klass* k) const { return klass()->is_subtype_of(k); }
inline bool oopDesc::is_instance() const { return klass()->oop_is_instance(); }
inline bool oopDesc::is_instanceMirror() const { return klass()->oop_is_instanceMirror(); }
inline bool oopDesc::is_instanceRef() const { return klass()->oop_is_instanceRef(); }
inline bool oopDesc::is_array() const { return klass()->oop_is_array(); }
inline bool oopDesc::is_objArray() const { return klass()->oop_is_objArray(); }
inline bool oopDesc::is_typeArray() const { return klass()->oop_is_typeArray(); }
inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; }
template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); }
inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); }
inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); }
inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); }
inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); }
inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); }
inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); }
inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
// Functions for getting and setting oops within instance objects.
// If the oops are compressed, the type passed to these overloaded functions
// is narrowOop. All functions are overloaded so they can be called by
// template functions without conditionals (the compiler instantiates via
// the right type and inlines the appopriate code).
inline bool oopDesc::is_null(oop obj) { return obj == NULL; }
inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
// Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
// offset from the heap base. Saving the check for null can save instructions
// in inner GC loops so these are separated.
inline bool check_obj_alignment(oop obj) {
return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
}
inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
assert(!is_null(v), "oop value can never be zero");
assert(check_obj_alignment(v), "Address not aligned");
assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
address base = Universe::narrow_oop_base();
int shift = Universe::narrow_oop_shift();
uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
uint64_t result = pd >> shift;
assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
assert(decode_heap_oop(result) == v, "reversibility");
return (narrowOop)result;
}
inline narrowOop oopDesc::encode_heap_oop(oop v) {
return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
}
inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
assert(!is_null(v), "narrow oop value can never be zero");
address base = Universe::narrow_oop_base();
int shift = Universe::narrow_oop_shift();
oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
assert(check_obj_alignment(result), err_msg("address not aligned: " PTR_FORMAT, (void*) result));
return result;
}
inline oop oopDesc::decode_heap_oop(narrowOop v) {
return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
}
inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
inline oop oopDesc::decode_heap_oop(oop v) { return v; }
// Load an oop out of the Java heap as is without decoding.
// Called by GC to check for null before decoding.
inline oop oopDesc::load_heap_oop(oop* p) { return *p; }
inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; }
// Load and decode an oop out of the Java heap into a wide oop.
inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; }
inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
return decode_heap_oop_not_null(*p);
}
// Load and decode an oop out of the heap accepting null
inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
return decode_heap_oop(*p);
}
// Store already encoded heap oop into the heap.
inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; }
inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; }
// Encode and store a heap oop.
inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
*p = encode_heap_oop_not_null(v);
}
inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
// Encode and store a heap oop allowing for null.
inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
*p = encode_heap_oop(v);
}
inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
// Store heap oop as is for volatile fields.
inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
OrderAccess::release_store_ptr(p, v);
}
inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
narrowOop v) {
OrderAccess::release_store(p, v);
}
inline void oopDesc::release_encode_store_heap_oop_not_null(
volatile narrowOop* p, oop v) {
// heap oop is not pointer sized.
OrderAccess::release_store(p, encode_heap_oop_not_null(v));
}
inline void oopDesc::release_encode_store_heap_oop_not_null(
volatile oop* p, oop v) {
OrderAccess::release_store_ptr(p, v);
}
inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
oop v) {
OrderAccess::release_store_ptr(p, v);
}
inline void oopDesc::release_encode_store_heap_oop(
volatile narrowOop* p, oop v) {
OrderAccess::release_store(p, encode_heap_oop(v));
}
// These functions are only used to exchange oop fields in instances,
// not headers.
inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
if (UseCompressedOops) {
// encode exchange value from oop to T
narrowOop val = encode_heap_oop(exchange_value);
narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
// decode old from T to oop
return decode_heap_oop(old);
} else {
return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
}
}
// In order to put or get a field out of an instance, must first check
// if the field has been compressed and uncompress it.
inline oop oopDesc::obj_field(int offset) const {
return UseCompressedOops ?
load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
load_decode_heap_oop(obj_field_addr<oop>(offset));
}
inline volatile oop oopDesc::obj_field_volatile(int offset) const {
volatile oop value = obj_field(offset);
OrderAccess::acquire();
return value;
}
inline void oopDesc::obj_field_put(int offset, oop value) {
UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
oop_store(obj_field_addr<oop>(offset), value);
}
inline Metadata* oopDesc::metadata_field(int offset) const {
return *metadata_field_addr(offset);
}
inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
*metadata_field_addr(offset) = value;
}
inline void oopDesc::obj_field_put_raw(int offset, oop value) {
UseCompressedOops ?
encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
encode_store_heap_oop(obj_field_addr<oop>(offset), value);
}
inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
OrderAccess::release();
obj_field_put(offset, value);
OrderAccess::fence();
}
inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); }
inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; }
inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); }
inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; }
inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); }
inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; }
inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); }
inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; }
inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); }
inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;}
inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); }
inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; }
inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); }
inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; }
inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); }
inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); }
inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
inline oop oopDesc::obj_field_acquire(int offset) const {
return UseCompressedOops ?
decode_heap_oop((narrowOop)
OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
: decode_heap_oop((oop)
OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
}
inline void oopDesc::release_obj_field_put(int offset, oop value) {
UseCompressedOops ?
oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
oop_store((volatile oop*) obj_field_addr<oop>(offset), value);
}
inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); }
inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); }
inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); }
inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); }
inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); }
inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); }
inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); }
inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); }
inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); }
inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); }
inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); }
inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); }
inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); }
inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); }
inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
inline address oopDesc::address_field_acquire(int offset) const { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
inline int oopDesc::size_given_klass(Klass* klass) {
int lh = klass->layout_helper();
int s;
// lh is now a value computed at class initialization that may hint
// at the size. For instances, this is positive and equal to the
// size. For arrays, this is negative and provides log2 of the
// array element size. For other oops, it is zero and thus requires
// a virtual call.
//
// We go to all this trouble because the size computation is at the
// heart of phase 2 of mark-compaction, and called for every object,
// alive or dead. So the speed here is equal in importance to the
// speed of allocation.
if (lh > Klass::_lh_neutral_value) {
if (!Klass::layout_helper_needs_slow_path(lh)) {
s = lh >> LogHeapWordSize; // deliver size scaled by wordSize
} else {
s = klass->oop_size(this);
}
} else if (lh <= Klass::_lh_neutral_value) {
// The most common case is instances; fall through if so.
if (lh < Klass::_lh_neutral_value) {
// Second most common case is arrays. We have to fetch the
// length of the array, shift (multiply) it appropriately,
// up to wordSize, add the header, and align to object size.
size_t size_in_bytes;
#ifdef _M_IA64
// The Windows Itanium Aug 2002 SDK hoists this load above
// the check for s < 0. An oop at the end of the heap will
// cause an access violation if this load is performed on a non
// array oop. Making the reference volatile prohibits this.
// (%%% please explain by what magic the length is actually fetched!)
volatile int *array_length;
array_length = (volatile int *)( (intptr_t)this +
arrayOopDesc::length_offset_in_bytes() );
assert(array_length > 0, "Integer arithmetic problem somewhere");
// Put into size_t to avoid overflow.
size_in_bytes = (size_t) array_length;
size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
#else
size_t array_length = (size_t) ((arrayOop)this)->length();
size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
#endif
size_in_bytes += Klass::layout_helper_header_size(lh);
// This code could be simplified, but by keeping array_header_in_bytes
// in units of bytes and doing it this way we can round up just once,
// skipping the intermediate round to HeapWordSize. Cast the result
// of round_to to size_t to guarantee unsigned division == right shift.
s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
HeapWordSize);
// UseParNewGC, UseParallelGC and UseG1GC can change the length field
// of an "old copy" of an object array in the young gen so it indicates
// the grey portion of an already copied array. This will cause the first
// disjunct below to fail if the two comparands are computed across such
// a concurrent change.
// UseParNewGC also runs with promotion labs (which look like int
// filler arrays) which are subject to changing their declared size
// when finally retiring a PLAB; this also can cause the first disjunct
// to fail for another worker thread that is concurrently walking the block
// offset table. Both these invariant failures are benign for their
// current uses; we relax the assertion checking to cover these two cases below:
// is_objArray() && is_forwarded() // covers first scenario above
// || is_typeArray() // covers second scenario above
// If and when UseParallelGC uses the same obj array oop stealing/chunking
// technique, we will need to suitably modify the assertion.
assert((s == klass->oop_size(this)) ||
(Universe::heap()->is_gc_active() &&
((is_typeArray() && UseParNewGC) ||
(is_objArray() && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
"wrong array object size");
} else {
// Must be zero, so bite the bullet and take the virtual call.
s = klass->oop_size(this);
}
}
assert(s % MinObjAlignment == 0, "alignment check");
assert(s > 0, "Bad size calculated");
return s;
}
inline int oopDesc::size() {
return size_given_klass(klass());
}
inline void update_barrier_set(void* p, oop v) {
assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
oopDesc::bs()->write_ref_field(p, v);
}
template <class T> inline void update_barrier_set_pre(T* p, oop v) {
oopDesc::bs()->write_ref_field_pre(p, v);
}
template <class T> inline void oop_store(T* p, oop v) {
if (always_do_update_barrier) {
oop_store((volatile T*)p, v);
} else {
update_barrier_set_pre(p, v);
oopDesc::encode_store_heap_oop(p, v);
update_barrier_set((void*)p, v); // cast away type
}
}
template <class T> inline void oop_store(volatile T* p, oop v) {
update_barrier_set_pre((T*)p, v); // cast away volatile
// Used by release_obj_field_put, so use release_store_ptr.
oopDesc::release_encode_store_heap_oop(p, v);
update_barrier_set((void*)p, v); // cast away type
}
// Should replace *addr = oop assignments where addr type depends on UseCompressedOops
// (without having to remember the function name this calls).
inline void oop_store_raw(HeapWord* addr, oop value) {
if (UseCompressedOops) {
oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
} else {
oopDesc::encode_store_heap_oop((oop*)addr, value);
}
}
inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
volatile HeapWord *dest,
oop compare_value,
bool prebarrier) {
if (UseCompressedOops) {
if (prebarrier) {
update_barrier_set_pre((narrowOop*)dest, exchange_value);
}
// encode exchange and compare value from oop to T
narrowOop val = encode_heap_oop(exchange_value);
narrowOop cmp = encode_heap_oop(compare_value);
narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
// decode old from T to oop
return decode_heap_oop(old);
} else {
if (prebarrier) {
update_barrier_set_pre((oop*)dest, exchange_value);
}
return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
}
}
// Used only for markSweep, scavenging
inline bool oopDesc::is_gc_marked() const {
return mark()->is_marked();
}
inline bool oopDesc::is_locked() const {
return mark()->is_locked();
}
inline bool oopDesc::is_unlocked() const {
return mark()->is_unlocked();
}
inline bool oopDesc::has_bias_pattern() const {
return mark()->has_bias_pattern();
}
// used only for asserts
inline bool oopDesc::is_oop(bool ignore_mark_word) const {
oop obj = (oop) this;
if (!check_obj_alignment(obj)) return false;
if (!Universe::heap()->is_in_reserved(obj)) return false;
// obj is aligned and accessible in heap
if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
// Header verification: the mark is typically non-NULL. If we're
// at a safepoint, it must not be null.
// Outside of a safepoint, the header could be changing (for example,
// another thread could be inflating a lock on this object).
if (ignore_mark_word) {
return true;
}
if (mark() != NULL) {
return true;
}
return !SafepointSynchronize::is_at_safepoint();
}
// used only for asserts
inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
return this == NULL ? true : is_oop(ignore_mark_word);
}
#ifndef PRODUCT
// used only for asserts
inline bool oopDesc::is_unlocked_oop() const {
if (!Universe::heap()->is_in_reserved(this)) return false;
return mark()->is_unlocked();
}
#endif // PRODUCT
inline void oopDesc::follow_contents(void) {
assert (is_gc_marked(), "should be marked");
klass()->oop_follow_contents(this);
}
// Used by scavengers
inline bool oopDesc::is_forwarded() const {
// The extra heap check is needed since the obj might be locked, in which case the
// mark would point to a stack location and have the sentinel bit cleared
return mark()->is_marked();
}
// Used by scavengers
inline void oopDesc::forward_to(oop p) {
assert(check_obj_alignment(p),
"forwarding to something not aligned");
assert(Universe::heap()->is_in_reserved(p),
"forwarding to something not in heap");
markOop m = markOopDesc::encode_pointer_as_mark(p);
assert(m->decode_pointer() == p, "encoding must be reversable");
set_mark(m);
}
// Used by parallel scavengers
inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
assert(check_obj_alignment(p),
"forwarding to something not aligned");
assert(Universe::heap()->is_in_reserved(p),
"forwarding to something not in heap");
markOop m = markOopDesc::encode_pointer_as_mark(p);
assert(m->decode_pointer() == p, "encoding must be reversable");
return cas_set_mark(m, compare) == compare;
}
// Note that the forwardee is not the same thing as the displaced_mark.
// The forwardee is used when copying during scavenge and mark-sweep.
// It does need to clear the low two locking- and GC-related bits.
inline oop oopDesc::forwardee() const {
return (oop) mark()->decode_pointer();
}
inline bool oopDesc::has_displaced_mark() const {
return mark()->has_displaced_mark_helper();
}
inline markOop oopDesc::displaced_mark() const {
return mark()->displaced_mark_helper();
}
inline void oopDesc::set_displaced_mark(markOop m) {
mark()->set_displaced_mark_helper(m);
}
// The following method needs to be MT safe.
inline uint oopDesc::age() const {
assert(!is_forwarded(), "Attempt to read age from forwarded mark");
if (has_displaced_mark()) {
return displaced_mark()->age();
} else {
return mark()->age();
}
}
inline void oopDesc::incr_age() {
assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
if (has_displaced_mark()) {
set_displaced_mark(displaced_mark()->incr_age());
} else {
set_mark(mark()->incr_age());
}
}
inline intptr_t oopDesc::identity_hash() {
// Fast case; if the object is unlocked and the hash value is set, no locking is needed
// Note: The mark must be read into local variable to avoid concurrent updates.
markOop mrk = mark();
if (mrk->is_unlocked() && !mrk->has_no_hash()) {
return mrk->hash();
} else if (mrk->is_marked()) {
return mrk->hash();
} else {
return slow_identity_hash();
}
}
inline int oopDesc::adjust_pointers() {
debug_only(int check_size = size());
int s = klass()->oop_adjust_pointers(this);
assert(s == check_size, "should be the same");
return s;
}
#define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
\
inline int oopDesc::oop_iterate(OopClosureType* blk) { \
SpecializationStats::record_call(); \
return klass()->oop_oop_iterate##nv_suffix(this, blk); \
} \
\
inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \
SpecializationStats::record_call(); \
return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \
}
inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
// The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
// the do_oop calls, but turns off all other features in ExtendedOopClosure.
NoHeaderExtendedOopClosure cl(blk);
return oop_iterate(&cl);
}
inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
NoHeaderExtendedOopClosure cl(blk);
return oop_iterate(&cl, mr);
}
ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
#if INCLUDE_ALL_GCS
#define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
\
inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) { \
SpecializationStats::record_call(); \
return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk); \
}
ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
#endif // INCLUDE_ALL_GCS
#endif // SHARE_VM_OOPS_OOP_INLINE_HPP
Other Java examples (source code examples)Here is a short list of links related to this Java oop.inline.hpp source code file: |
The search page
Other Java source code examples at this package level
Click here to learn more about this project
