aoqi@0: /*
aoqi@0:  * Copyright (c) 2001, 2010, 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: #ifndef SHARE_VM_MEMORY_DEFNEWGENERATION_INLINE_HPP
aoqi@0: #define SHARE_VM_MEMORY_DEFNEWGENERATION_INLINE_HPP
aoqi@0: 
aoqi@0: #include "memory/cardTableRS.hpp"
aoqi@0: #include "memory/defNewGeneration.hpp"
aoqi@0: #include "memory/space.hpp"
aoqi@0: 
aoqi@0: // Methods of protected closure types
aoqi@0: 
aoqi@0: template <class T>
aoqi@0: inline void DefNewGeneration::KeepAliveClosure::do_oop_work(T* p) {
aoqi@0: #ifdef ASSERT
aoqi@0:   {
aoqi@0:     // We never expect to see a null reference being processed
aoqi@0:     // as a weak reference.
aoqi@0:     assert (!oopDesc::is_null(*p), "expected non-null ref");
aoqi@0:     oop obj = oopDesc::load_decode_heap_oop_not_null(p);
aoqi@0:     assert (obj->is_oop(), "expected an oop while scanning weak refs");
aoqi@0:   }
aoqi@0: #endif // ASSERT
aoqi@0: 
aoqi@0:   _cl->do_oop_nv(p);
aoqi@0: 
aoqi@0:   // Card marking is trickier for weak refs.
aoqi@0:   // This oop is a 'next' field which was filled in while we
aoqi@0:   // were discovering weak references. While we might not need
aoqi@0:   // to take a special action to keep this reference alive, we
aoqi@0:   // will need to dirty a card as the field was modified.
aoqi@0:   //
aoqi@0:   // Alternatively, we could create a method which iterates through
aoqi@0:   // each generation, allowing them in turn to examine the modified
aoqi@0:   // field.
aoqi@0:   //
aoqi@0:   // We could check that p is also in an older generation, but
aoqi@0:   // dirty cards in the youngest gen are never scanned, so the
aoqi@0:   // extra check probably isn't worthwhile.
aoqi@0:   if (Universe::heap()->is_in_reserved(p)) {
aoqi@0:     oop obj = oopDesc::load_decode_heap_oop_not_null(p);
aoqi@0:     _rs->inline_write_ref_field_gc(p, obj);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: template <class T>
aoqi@0: inline void DefNewGeneration::FastKeepAliveClosure::do_oop_work(T* p) {
aoqi@0: #ifdef ASSERT
aoqi@0:   {
aoqi@0:     // We never expect to see a null reference being processed
aoqi@0:     // as a weak reference.
aoqi@0:     assert (!oopDesc::is_null(*p), "expected non-null ref");
aoqi@0:     oop obj = oopDesc::load_decode_heap_oop_not_null(p);
aoqi@0:     assert (obj->is_oop(), "expected an oop while scanning weak refs");
aoqi@0:   }
aoqi@0: #endif // ASSERT
aoqi@0: 
aoqi@0:   _cl->do_oop_nv(p);
aoqi@0: 
aoqi@0:   // Optimized for Defnew generation if it's the youngest generation:
aoqi@0:   // we set a younger_gen card if we have an older->youngest
aoqi@0:   // generation pointer.
aoqi@0:   oop obj = oopDesc::load_decode_heap_oop_not_null(p);
aoqi@0:   if (((HeapWord*)obj < _boundary) && Universe::heap()->is_in_reserved(p)) {
aoqi@0:     _rs->inline_write_ref_field_gc(p, obj);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: #endif // SHARE_VM_MEMORY_DEFNEWGENERATION_INLINE_HPP