aoqi@0: /*
aoqi@0:  * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "classfile/classLoaderData.hpp"
aoqi@0: #include "memory/cardTableRS.hpp"
aoqi@0: #include "memory/genRemSet.hpp"
aoqi@0: 
aoqi@0: // This kind of "BarrierSet" allows a "CollectedHeap" to detect and
aoqi@0: // enumerate ref fields that have been modified (since the last
aoqi@0: // enumeration.)
aoqi@0: 
aoqi@0: uintx GenRemSet::max_alignment_constraint(Name nm) {
aoqi@0:   assert(nm == GenRemSet::CardTable, "Unrecognized GenRemSet type.");
aoqi@0:   return CardTableRS::ct_max_alignment_constraint();
aoqi@0: }
aoqi@0: 
aoqi@0: class HasAccumulatedModifiedOopsClosure : public KlassClosure {
aoqi@0:   bool _found;
aoqi@0:  public:
aoqi@0:   HasAccumulatedModifiedOopsClosure() : _found(false) {}
aoqi@0:   void do_klass(Klass* klass) {
aoqi@0:     if (_found) {
aoqi@0:       return;
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (klass->has_accumulated_modified_oops()) {
aoqi@0:       _found = true;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   bool found() {
aoqi@0:     return _found;
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: bool KlassRemSet::mod_union_is_clear() {
aoqi@0:   HasAccumulatedModifiedOopsClosure closure;
aoqi@0:   ClassLoaderDataGraph::classes_do(&closure);
aoqi@0: 
aoqi@0:   return !closure.found();
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: class ClearKlassModUnionClosure : public KlassClosure {
aoqi@0:  public:
aoqi@0:   void do_klass(Klass* klass) {
aoqi@0:     if (klass->has_accumulated_modified_oops()) {
aoqi@0:       klass->clear_accumulated_modified_oops();
aoqi@0:     }
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: void KlassRemSet::clear_mod_union() {
aoqi@0:   ClearKlassModUnionClosure closure;
aoqi@0:   ClassLoaderDataGraph::classes_do(&closure);
aoqi@0: }