1 /*
2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #ifndef SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP
26 #define SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP
27
28 #include "memory/cardTableRS.hpp"
29 #include "memory/defNewGeneration.hpp"
30 #include "memory/genCollectedHeap.hpp"
31 #include "memory/genOopClosures.hpp"
32 #include "memory/genRemSet.hpp"
33 #include "memory/generation.hpp"
34 #include "memory/sharedHeap.hpp"
35 #include "memory/space.hpp"
36
37 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :
38 OopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) {
39 set_generation(gen);
40 }
41
42 inline void OopsInGenClosure::set_generation(Generation* gen) {
43 _gen = gen;
44 _gen_boundary = _gen->reserved().start();
45 // Barrier set for the heap, must be set after heap is initialized
46 if (_rs == NULL) {
47 GenRemSet* rs = SharedHeap::heap()->rem_set();
48 assert(rs->rs_kind() == GenRemSet::CardTable, "Wrong rem set kind");
49 _rs = (CardTableRS*)rs;
50 }
51 }
52
53 template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
54 assert(generation()->is_in_reserved(p), "expected ref in generation");
55 T heap_oop = oopDesc::load_heap_oop(p);
56 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
57 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
58 // If p points to a younger generation, mark the card.
59 if ((HeapWord*)obj < _gen_boundary) {
60 _rs->inline_write_ref_field_gc(p, obj);
61 }
62 }
63
64 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
65 assert(generation()->is_in_reserved(p), "expected ref in generation");
66 T heap_oop = oopDesc::load_heap_oop(p);
67 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
68 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
69 // If p points to a younger generation, mark the card.
70 if ((HeapWord*)obj < gen_boundary()) {
71 rs()->write_ref_field_gc_par(p, obj);
72 }
73 }
74
75 // NOTE! Any changes made here should also be made
76 // in FastScanClosure::do_oop_work()
77 template <class T> inline void ScanClosure::do_oop_work(T* p) {
78 T heap_oop = oopDesc::load_heap_oop(p);
79 // Should we copy the obj?
80 if (!oopDesc::is_null(heap_oop)) {
81 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
82 if ((HeapWord*)obj < _boundary) {
83 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
84 oop new_obj = obj->is_forwarded() ? obj->forwardee()
85 : _g->copy_to_survivor_space(obj);
86 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
87 }
88 if (_gc_barrier) {
89 // Now call parent closure
90 do_barrier(p);
91 }
92 }
93 }
94
95 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); }
96 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
97
98 // NOTE! Any changes made here should also be made
99 // in ScanClosure::do_oop_work()
100 template <class T> inline void FastScanClosure::do_oop_work(T* p) {
101 T heap_oop = oopDesc::load_heap_oop(p);
102 // Should we copy the obj?
103 if (!oopDesc::is_null(heap_oop)) {
104 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
105 if ((HeapWord*)obj < _boundary) {
106 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
107 oop new_obj = obj->is_forwarded() ? obj->forwardee()
108 : _g->copy_to_survivor_space(obj);
109 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
110 if (_gc_barrier) {
111 // Now call parent closure
112 do_barrier(p);
113 }
114 }
115 }
116 }
117
118 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); }
119 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
120
121 // Note similarity to ScanClosure; the difference is that
122 // the barrier set is taken care of outside this closure.
123 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
124 assert(!oopDesc::is_null(*p), "null weak reference?");
125 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
126 // weak references are sometimes scanned twice; must check
127 // that to-space doesn't already contain this object
128 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
129 oop new_obj = obj->is_forwarded() ? obj->forwardee()
130 : _g->copy_to_survivor_space(obj);
131 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
132 }
133 }
134
135 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); }
136 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
137
138 #endif // SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP