Mercurial > hg > truffle
view src/share/vm/oops/instanceKlassKlass.hpp @ 3917:eca1193ca245
4965777: GC changes to support use of discovered field for pending references
Summary: If and when the reference handler thread is able to use the discovered field to link reference objects in its pending list, so will GC. In that case, GC will scan through this field once a reference object has been placed on the pending list, but not scan that field before that stage, as the field is used by the concurrent GC thread to link discovered objects. When ReferenceHandleR thread does not use the discovered field for the purpose of linking the elements in the pending list, as would be the case in older JDKs, the JVM will fall back to the old behaviour of using the next field for that purpose.
Reviewed-by: jcoomes, mchung, stefank
| author | ysr |
|---|---|
| date | Wed, 07 Sep 2011 13:55:42 -0700 |
| parents | c7f3d0b4570f |
| children | 49036505ab5f |
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/* * Copyright (c) 1997, 2011, 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_INSTANCEKLASSKLASS_HPP #define SHARE_VM_OOPS_INSTANCEKLASSKLASS_HPP #include "oops/klassKlass.hpp" // An instanceKlassKlass is the klass of an instanceKlass class instanceKlassKlass : public klassKlass { public: // Dispatched operation bool oop_is_klass() const { return true; } bool oop_is_instanceKlass() const { return true; } int oop_size(oop obj) const; int klass_oop_size() const { return object_size(); } // Allocation DEFINE_ALLOCATE_PERMANENT(instanceKlassKlass); static klassOop create_klass(TRAPS); klassOop allocate_instance_klass(Symbol* name, int vtable_len, int itable_len, int static_field_size, unsigned int nonstatic_oop_map_count, ReferenceType rt, TRAPS); // Casting from klassOop static instanceKlassKlass* cast(klassOop k) { assert(k->klass_part()->oop_is_klass(), "cast to instanceKlassKlass"); return (instanceKlassKlass*) k->klass_part(); } // Sizing static int header_size() { return oopDesc::header_size() + sizeof(instanceKlassKlass)/HeapWordSize; } int object_size() const { return align_object_size(header_size()); } // Garbage collection void oop_follow_contents(oop obj); int oop_adjust_pointers(oop obj); bool oop_is_parsable(oop obj) const; // Parallel Scavenge and Parallel Old PARALLEL_GC_DECLS // Iterators int oop_oop_iterate(oop obj, OopClosure* blk); int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr); private: // Apply closure to the InstanceKlass oops that are outside the java heap. inline void iterate_c_heap_oops(instanceKlass* ik, OopClosure* closure); public: // Printing void oop_print_value_on(oop obj, outputStream* st); #ifndef PRODUCT void oop_print_on(oop obj, outputStream* st); #endif // Verification const char* internal_name() const; void oop_verify_on(oop obj, outputStream* st); // tells whether obj is partially constructed (gc during class loading) bool oop_partially_loaded(oop obj) const; void oop_set_partially_loaded(oop obj); }; #endif // SHARE_VM_OOPS_INSTANCEKLASSKLASS_HPP