duke@435: /* duke@435: * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved. duke@435: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. duke@435: * duke@435: * This code is free software; you can redistribute it and/or modify it duke@435: * under the terms of the GNU General Public License version 2 only, as duke@435: * published by the Free Software Foundation. duke@435: * duke@435: * This code is distributed in the hope that it will be useful, but WITHOUT duke@435: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or duke@435: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License duke@435: * version 2 for more details (a copy is included in the LICENSE file that duke@435: * accompanied this code). duke@435: * duke@435: * You should have received a copy of the GNU General Public License version duke@435: * 2 along with this work; if not, write to the Free Software Foundation, duke@435: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. duke@435: * duke@435: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, duke@435: * CA 95054 USA or visit www.sun.com if you need additional information or duke@435: * have any questions. duke@435: * duke@435: */ duke@435: duke@435: // Implementation of all inlined member functions defined in oop.hpp duke@435: // We need a separate file to avoid circular references duke@435: duke@435: duke@435: inline void oopDesc::release_set_mark(markOop m) { duke@435: OrderAccess::release_store_ptr(&_mark, m); duke@435: } duke@435: duke@435: inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) { duke@435: return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark); duke@435: } duke@435: duke@435: inline void oopDesc::set_klass(klassOop k) { duke@435: // since klasses are promoted no store check is needed duke@435: assert(Universe::is_bootstrapping() || k != NULL, "must be a real klassOop"); duke@435: assert(Universe::is_bootstrapping() || k->is_klass(), "not a klassOop"); duke@435: oop_store_without_check((oop*) &_klass, (oop) k); duke@435: } duke@435: duke@435: inline void oopDesc::set_klass_to_list_ptr(oop k) { duke@435: // This is only to be used during GC, for from-space objects, so no duke@435: // barrier is needed. duke@435: _klass = (klassOop)k; duke@435: } duke@435: duke@435: inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); } duke@435: inline Klass* oopDesc::blueprint() const { return klass()->klass_part(); } duke@435: duke@435: inline bool oopDesc::is_a(klassOop k) const { return blueprint()->is_subtype_of(k); } duke@435: duke@435: inline bool oopDesc::is_instance() const { return blueprint()->oop_is_instance(); } duke@435: inline bool oopDesc::is_instanceRef() const { return blueprint()->oop_is_instanceRef(); } duke@435: inline bool oopDesc::is_array() const { return blueprint()->oop_is_array(); } duke@435: inline bool oopDesc::is_objArray() const { return blueprint()->oop_is_objArray(); } duke@435: inline bool oopDesc::is_typeArray() const { return blueprint()->oop_is_typeArray(); } duke@435: inline bool oopDesc::is_javaArray() const { return blueprint()->oop_is_javaArray(); } duke@435: inline bool oopDesc::is_symbol() const { return blueprint()->oop_is_symbol(); } duke@435: inline bool oopDesc::is_klass() const { return blueprint()->oop_is_klass(); } duke@435: inline bool oopDesc::is_thread() const { return blueprint()->oop_is_thread(); } duke@435: inline bool oopDesc::is_method() const { return blueprint()->oop_is_method(); } duke@435: inline bool oopDesc::is_constMethod() const { return blueprint()->oop_is_constMethod(); } duke@435: inline bool oopDesc::is_methodData() const { return blueprint()->oop_is_methodData(); } duke@435: inline bool oopDesc::is_constantPool() const { return blueprint()->oop_is_constantPool(); } duke@435: inline bool oopDesc::is_constantPoolCache() const { return blueprint()->oop_is_constantPoolCache(); } duke@435: inline bool oopDesc::is_compiledICHolder() const { return blueprint()->oop_is_compiledICHolder(); } duke@435: duke@435: inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; } duke@435: duke@435: inline oop* oopDesc::obj_field_addr(int offset) const { return (oop*) field_base(offset); } duke@435: inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); } duke@435: inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); } duke@435: inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); } duke@435: inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); } duke@435: inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); } duke@435: inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); } duke@435: inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); } duke@435: inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); } duke@435: duke@435: inline oop oopDesc::obj_field(int offset) const { return *obj_field_addr(offset); } duke@435: inline void oopDesc::obj_field_put(int offset, oop value) { oop_store(obj_field_addr(offset), value); } duke@435: duke@435: inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); } duke@435: inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; } duke@435: duke@435: inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); } duke@435: inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; } duke@435: duke@435: inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); } duke@435: inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; } duke@435: duke@435: inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); } duke@435: inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; } duke@435: duke@435: inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); } duke@435: inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;} duke@435: duke@435: inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); } duke@435: inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; } duke@435: duke@435: inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); } duke@435: inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; } duke@435: duke@435: inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); } duke@435: inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; } duke@435: duke@435: inline oop oopDesc::obj_field_acquire(int offset) const { return (oop)OrderAccess::load_ptr_acquire(obj_field_addr(offset)); } duke@435: inline void oopDesc::release_obj_field_put(int offset, oop value) { oop_store((volatile oop*)obj_field_addr(offset), value); } duke@435: duke@435: inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); } duke@435: inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); } duke@435: duke@435: inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); } duke@435: inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); } duke@435: duke@435: inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); } duke@435: inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); } duke@435: duke@435: inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); } duke@435: inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); } duke@435: duke@435: inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); } duke@435: inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); } duke@435: duke@435: inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); } duke@435: inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); } duke@435: duke@435: inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); } duke@435: inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); } duke@435: duke@435: inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); } duke@435: inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); } duke@435: duke@435: duke@435: inline int oopDesc::size_given_klass(Klass* klass) { duke@435: int lh = klass->layout_helper(); duke@435: int s = lh >> LogHeapWordSize; // deliver size scaled by wordSize duke@435: duke@435: // lh is now a value computed at class initialization that may hint duke@435: // at the size. For instances, this is positive and equal to the duke@435: // size. For arrays, this is negative and provides log2 of the duke@435: // array element size. For other oops, it is zero and thus requires duke@435: // a virtual call. duke@435: // duke@435: // We go to all this trouble because the size computation is at the duke@435: // heart of phase 2 of mark-compaction, and called for every object, duke@435: // alive or dead. So the speed here is equal in importance to the duke@435: // speed of allocation. duke@435: duke@435: if (lh <= Klass::_lh_neutral_value) { duke@435: // The most common case is instances; fall through if so. duke@435: if (lh < Klass::_lh_neutral_value) { duke@435: // Second most common case is arrays. We have to fetch the duke@435: // length of the array, shift (multiply) it appropriately, duke@435: // up to wordSize, add the header, and align to object size. duke@435: size_t size_in_bytes; duke@435: #ifdef _M_IA64 duke@435: // The Windows Itanium Aug 2002 SDK hoists this load above duke@435: // the check for s < 0. An oop at the end of the heap will duke@435: // cause an access violation if this load is performed on a non duke@435: // array oop. Making the reference volatile prohibits this. duke@435: // (%%% please explain by what magic the length is actually fetched!) duke@435: volatile int *array_length; duke@435: array_length = (volatile int *)( (intptr_t)this + duke@435: arrayOopDesc::length_offset_in_bytes() ); duke@435: assert(array_length > 0, "Integer arithmetic problem somewhere"); duke@435: // Put into size_t to avoid overflow. duke@435: size_in_bytes = (size_t) array_length; duke@435: size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh); duke@435: #else duke@435: size_t array_length = (size_t) ((arrayOop)this)->length(); duke@435: size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh); duke@435: #endif duke@435: size_in_bytes += Klass::layout_helper_header_size(lh); duke@435: duke@435: // This code could be simplified, but by keeping array_header_in_bytes duke@435: // in units of bytes and doing it this way we can round up just once, duke@435: // skipping the intermediate round to HeapWordSize. Cast the result duke@435: // of round_to to size_t to guarantee unsigned division == right shift. duke@435: s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) / duke@435: HeapWordSize); duke@435: duke@435: // UseParNewGC can change the length field of an "old copy" of an object duke@435: // array in the young gen so it indicates the stealable portion of duke@435: // an already copied array. This will cause the first disjunct below duke@435: // to fail if the sizes are computed across such a concurrent change. duke@435: // UseParNewGC also runs with promotion labs (which look like int duke@435: // filler arrays) which are subject to changing their declared size duke@435: // when finally retiring a PLAB; this also can cause the first disjunct duke@435: // to fail for another worker thread that is concurrently walking the block duke@435: // offset table. Both these invariant failures are benign for their duke@435: // current uses; we relax the assertion checking to cover these two cases below: duke@435: // is_objArray() && is_forwarded() // covers first scenario above duke@435: // || is_typeArray() // covers second scenario above duke@435: // If and when UseParallelGC uses the same obj array oop stealing/chunking duke@435: // technique, or when G1 is integrated (and currently uses this array chunking duke@435: // technique) we will need to suitably modify the assertion. duke@435: assert((s == klass->oop_size(this)) || duke@435: (((UseParNewGC || UseParallelGC) && duke@435: Universe::heap()->is_gc_active()) && duke@435: (is_typeArray() || duke@435: (is_objArray() && is_forwarded()))), duke@435: "wrong array object size"); duke@435: } else { duke@435: // Must be zero, so bite the bullet and take the virtual call. duke@435: s = klass->oop_size(this); duke@435: } duke@435: } duke@435: duke@435: assert(s % MinObjAlignment == 0, "alignment check"); duke@435: assert(s > 0, "Bad size calculated"); duke@435: return s; duke@435: } duke@435: duke@435: duke@435: inline int oopDesc::size() { duke@435: return size_given_klass(blueprint()); duke@435: } duke@435: duke@435: inline bool oopDesc::is_parsable() { duke@435: return blueprint()->oop_is_parsable(this); duke@435: } duke@435: duke@435: duke@435: inline void update_barrier_set(oop *p, oop v) { duke@435: assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!"); duke@435: oopDesc::bs()->write_ref_field(p, v); duke@435: } duke@435: duke@435: duke@435: inline void oop_store(oop* p, oop v) { duke@435: if (always_do_update_barrier) { duke@435: oop_store((volatile oop*)p, v); duke@435: } else { duke@435: *p = v; duke@435: update_barrier_set(p, v); duke@435: } duke@435: } duke@435: duke@435: inline void oop_store(volatile oop* p, oop v) { duke@435: // Used by release_obj_field_put, so use release_store_ptr. duke@435: OrderAccess::release_store_ptr(p, v); duke@435: update_barrier_set((oop *)p, v); duke@435: } duke@435: duke@435: inline void oop_store_without_check(oop* p, oop v) { duke@435: // XXX YSR FIX ME!!! duke@435: if (always_do_update_barrier) { duke@435: oop_store(p, v); duke@435: } else { duke@435: assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier(p, v), duke@435: "oop store without store check failed"); duke@435: *p = v; duke@435: } duke@435: } duke@435: duke@435: // When it absolutely has to get there. duke@435: inline void oop_store_without_check(volatile oop* p, oop v) { duke@435: // XXX YSR FIX ME!!! duke@435: if (always_do_update_barrier) { duke@435: oop_store(p, v); duke@435: } else { duke@435: assert(!Universe::heap()->barrier_set()-> duke@435: write_ref_needs_barrier((oop *)p, v), duke@435: "oop store without store check failed"); duke@435: OrderAccess::release_store_ptr(p, v); duke@435: } duke@435: } duke@435: duke@435: duke@435: // Used only for markSweep, scavenging duke@435: inline bool oopDesc::is_gc_marked() const { duke@435: return mark()->is_marked(); duke@435: } duke@435: duke@435: inline bool oopDesc::is_locked() const { duke@435: return mark()->is_locked(); duke@435: } duke@435: duke@435: inline bool oopDesc::is_unlocked() const { duke@435: return mark()->is_unlocked(); duke@435: } duke@435: duke@435: inline bool oopDesc::has_bias_pattern() const { duke@435: return mark()->has_bias_pattern(); duke@435: } duke@435: duke@435: inline bool check_obj_alignment(oop obj) { duke@435: return (intptr_t)obj % MinObjAlignmentInBytes == 0; duke@435: } duke@435: duke@435: duke@435: // used only for asserts duke@435: inline bool oopDesc::is_oop(bool ignore_mark_word) const { duke@435: oop obj = (oop) this; duke@435: if (!check_obj_alignment(obj)) return false; duke@435: if (!Universe::heap()->is_in_reserved(obj)) return false; duke@435: // obj is aligned and accessible in heap duke@435: // try to find metaclass cycle safely without seg faulting on bad input duke@435: // we should reach klassKlassObj by following klass link at most 3 times duke@435: for (int i = 0; i < 3; i++) { duke@435: obj = obj->klass(); duke@435: // klass should be aligned and in permspace duke@435: if (!check_obj_alignment(obj)) return false; duke@435: if (!Universe::heap()->is_in_permanent(obj)) return false; duke@435: } duke@435: if (obj != Universe::klassKlassObj()) { duke@435: // During a dump, the _klassKlassObj moved to a shared space. duke@435: if (DumpSharedSpaces && Universe::klassKlassObj()->is_shared()) { duke@435: return true; duke@435: } duke@435: return false; duke@435: } duke@435: duke@435: // Header verification: the mark is typically non-NULL. If we're duke@435: // at a safepoint, it must not be null. duke@435: // Outside of a safepoint, the header could be changing (for example, duke@435: // another thread could be inflating a lock on this object). duke@435: if (ignore_mark_word) { duke@435: return true; duke@435: } duke@435: if (mark() != NULL) { duke@435: return true; duke@435: } duke@435: return !SafepointSynchronize::is_at_safepoint(); duke@435: } duke@435: duke@435: duke@435: // used only for asserts duke@435: inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const { duke@435: return this == NULL ? true : is_oop(ignore_mark_word); duke@435: } duke@435: duke@435: #ifndef PRODUCT duke@435: // used only for asserts duke@435: inline bool oopDesc::is_unlocked_oop() const { duke@435: if (!Universe::heap()->is_in_reserved(this)) return false; duke@435: return mark()->is_unlocked(); duke@435: } duke@435: duke@435: duke@435: #endif // PRODUCT duke@435: duke@435: inline void oopDesc::follow_header() { duke@435: MarkSweep::mark_and_push((oop*)&_klass); duke@435: } duke@435: duke@435: inline void oopDesc::follow_contents() { duke@435: assert (is_gc_marked(), "should be marked"); duke@435: blueprint()->oop_follow_contents(this); duke@435: } duke@435: duke@435: duke@435: // Used by scavengers duke@435: duke@435: inline bool oopDesc::is_forwarded() const { duke@435: // The extra heap check is needed since the obj might be locked, in which case the duke@435: // mark would point to a stack location and have the sentinel bit cleared duke@435: return mark()->is_marked(); duke@435: } duke@435: duke@435: duke@435: // Used by scavengers duke@435: inline void oopDesc::forward_to(oop p) { duke@435: assert(Universe::heap()->is_in_reserved(p), duke@435: "forwarding to something not in heap"); duke@435: markOop m = markOopDesc::encode_pointer_as_mark(p); duke@435: assert(m->decode_pointer() == p, "encoding must be reversable"); duke@435: set_mark(m); duke@435: } duke@435: duke@435: // Used by parallel scavengers duke@435: inline bool oopDesc::cas_forward_to(oop p, markOop compare) { duke@435: assert(Universe::heap()->is_in_reserved(p), duke@435: "forwarding to something not in heap"); duke@435: markOop m = markOopDesc::encode_pointer_as_mark(p); duke@435: assert(m->decode_pointer() == p, "encoding must be reversable"); duke@435: return cas_set_mark(m, compare) == compare; duke@435: } duke@435: duke@435: // Note that the forwardee is not the same thing as the displaced_mark. duke@435: // The forwardee is used when copying during scavenge and mark-sweep. duke@435: // It does need to clear the low two locking- and GC-related bits. duke@435: inline oop oopDesc::forwardee() const { return (oop) mark()->decode_pointer(); } duke@435: duke@435: duke@435: inline bool oopDesc::has_displaced_mark() const { duke@435: return mark()->has_displaced_mark_helper(); duke@435: } duke@435: duke@435: inline markOop oopDesc::displaced_mark() const { duke@435: return mark()->displaced_mark_helper(); duke@435: } duke@435: duke@435: inline void oopDesc::set_displaced_mark(markOop m) { duke@435: mark()->set_displaced_mark_helper(m); duke@435: } duke@435: duke@435: // The following method needs to be MT safe. duke@435: inline int oopDesc::age() const { duke@435: assert(!is_forwarded(), "Attempt to read age from forwarded mark"); duke@435: if (has_displaced_mark()) { duke@435: return displaced_mark()->age(); duke@435: } else { duke@435: return mark()->age(); duke@435: } duke@435: } duke@435: duke@435: inline void oopDesc::incr_age() { duke@435: assert(!is_forwarded(), "Attempt to increment age of forwarded mark"); duke@435: if (has_displaced_mark()) { duke@435: set_displaced_mark(displaced_mark()->incr_age()); duke@435: } else { duke@435: set_mark(mark()->incr_age()); duke@435: } duke@435: } duke@435: duke@435: duke@435: inline intptr_t oopDesc::identity_hash() { duke@435: // Fast case; if the object is unlocked and the hash value is set, no locking is needed duke@435: // Note: The mark must be read into local variable to avoid concurrent updates. duke@435: markOop mrk = mark(); duke@435: if (mrk->is_unlocked() && !mrk->has_no_hash()) { duke@435: return mrk->hash(); duke@435: } else if (mrk->is_marked()) { duke@435: return mrk->hash(); duke@435: } else { duke@435: return slow_identity_hash(); duke@435: } duke@435: } duke@435: duke@435: duke@435: inline void oopDesc::oop_iterate_header(OopClosure* blk) { duke@435: blk->do_oop((oop*)&_klass); duke@435: } duke@435: duke@435: duke@435: inline void oopDesc::oop_iterate_header(OopClosure* blk, MemRegion mr) { duke@435: if (mr.contains(&_klass)) blk->do_oop((oop*)&_klass); duke@435: } duke@435: duke@435: duke@435: inline int oopDesc::adjust_pointers() { duke@435: debug_only(int check_size = size()); duke@435: int s = blueprint()->oop_adjust_pointers(this); duke@435: assert(s == check_size, "should be the same"); duke@435: return s; duke@435: } duke@435: duke@435: inline void oopDesc::adjust_header() { duke@435: MarkSweep::adjust_pointer((oop*)&_klass); duke@435: } duke@435: duke@435: #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ duke@435: \ duke@435: inline int oopDesc::oop_iterate(OopClosureType* blk) { \ duke@435: SpecializationStats::record_call(); \ duke@435: return blueprint()->oop_oop_iterate##nv_suffix(this, blk); \ duke@435: } \ duke@435: \ duke@435: inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \ duke@435: SpecializationStats::record_call(); \ duke@435: return blueprint()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \ duke@435: } duke@435: duke@435: ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN) duke@435: ALL_OOP_OOP_ITERATE_CLOSURES_3(OOP_ITERATE_DEFN) duke@435: duke@435: duke@435: inline bool oopDesc::is_shared() const { duke@435: return CompactingPermGenGen::is_shared(this); duke@435: } duke@435: duke@435: inline bool oopDesc::is_shared_readonly() const { duke@435: return CompactingPermGenGen::is_shared_readonly(this); duke@435: } duke@435: duke@435: inline bool oopDesc::is_shared_readwrite() const { duke@435: return CompactingPermGenGen::is_shared_readwrite(this); duke@435: }