| /* |
| * Copyright (c) 2001, 2017, 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_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP |
| #define SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP |
| |
| #include "gc/serial/defNewGeneration.hpp" |
| #include "gc/shared/cardTableRS.hpp" |
| #include "gc/shared/genCollectedHeap.hpp" |
| #include "gc/shared/genOopClosures.inline.hpp" |
| #include "gc/shared/space.hpp" |
| |
| // Methods of protected closure types |
| |
| template <class T> |
| inline void DefNewGeneration::KeepAliveClosure::do_oop_work(T* p) { |
| #ifdef ASSERT |
| { |
| // We never expect to see a null reference being processed |
| // as a weak reference. |
| assert (!oopDesc::is_null(*p), "expected non-null ref"); |
| oop obj = oopDesc::load_decode_heap_oop_not_null(p); |
| assert (oopDesc::is_oop(obj), "expected an oop while scanning weak refs"); |
| } |
| #endif // ASSERT |
| |
| _cl->do_oop_nv(p); |
| |
| // Card marking is trickier for weak refs. |
| // This oop is a 'next' field which was filled in while we |
| // were discovering weak references. While we might not need |
| // to take a special action to keep this reference alive, we |
| // will need to dirty a card as the field was modified. |
| // |
| // Alternatively, we could create a method which iterates through |
| // each generation, allowing them in turn to examine the modified |
| // field. |
| // |
| // We could check that p is also in the old generation, but |
| // dirty cards in the young gen are never scanned, so the |
| // extra check probably isn't worthwhile. |
| if (GenCollectedHeap::heap()->is_in_reserved(p)) { |
| oop obj = oopDesc::load_decode_heap_oop_not_null(p); |
| _rs->inline_write_ref_field_gc(p, obj); |
| } |
| } |
| |
| template <class T> |
| inline void DefNewGeneration::FastKeepAliveClosure::do_oop_work(T* p) { |
| #ifdef ASSERT |
| { |
| // We never expect to see a null reference being processed |
| // as a weak reference. |
| assert (!oopDesc::is_null(*p), "expected non-null ref"); |
| oop obj = oopDesc::load_decode_heap_oop_not_null(p); |
| assert (oopDesc::is_oop(obj), "expected an oop while scanning weak refs"); |
| } |
| #endif // ASSERT |
| |
| _cl->do_oop_nv(p); |
| |
| // Optimized for Defnew generation if it's the youngest generation: |
| // we set a younger_gen card if we have an older->youngest |
| // generation pointer. |
| oop obj = oopDesc::load_decode_heap_oop_not_null(p); |
| if (((HeapWord*)obj < _boundary) && GenCollectedHeap::heap()->is_in_reserved(p)) { |
| _rs->inline_write_ref_field_gc(p, obj); |
| } |
| } |
| |
| #endif // SHARE_VM_GC_SERIAL_DEFNEWGENERATION_INLINE_HPP |