1 /*
2 * Copyright (c) 2001, 2015, 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.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP
26 #define SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP
27
28 #include "gc/serial/defNewGeneration.hpp"
29 #include "gc/shared/cardTableRS.hpp"
30 #include "gc/shared/genCollectedHeap.hpp"
31 #include "gc/shared/genOopClosures.hpp"
32 #include "gc/shared/genRemSet.hpp"
33 #include "gc/shared/generation.hpp"
34 #include "gc/shared/space.hpp"
35
36 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :
37 ExtendedOopClosure(gen->ref_processor()), _gen(NULL), _rs(NULL) {
38 set_generation(gen);
39 }
40
41 inline void OopsInGenClosure::set_generation(Generation* gen) {
42 assert(_gen == NULL, "Generation already initialized");
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 = GenCollectedHeap::heap()->rem_set();
48 _rs = (CardTableRS*)rs;
49 }
50 }
51
52 inline void OopsInGenClosure::assert_generation(Generation* gen) {
53 assert(_gen == gen, "Generations mismatch. Fix it now!!");
54 }
55
56 template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
57 assert(generation()->is_in_reserved(p), "expected ref in generation");
58 T heap_oop = oopDesc::load_heap_oop(p);
59 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
60 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
61 // If p points to a younger generation, mark the card.
62 if ((HeapWord*)obj < _gen_boundary) {
63 _rs->inline_write_ref_field_gc(p, obj);
64 }
65 }
66
67 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
68 assert(generation()->is_in_reserved(p), "expected ref in generation");
69 T heap_oop = oopDesc::load_heap_oop(p);
70 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
71 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
72 // If p points to a younger generation, mark the card.
73 if ((HeapWord*)obj < gen_boundary()) {
74 rs()->write_ref_field_gc_par(p, obj);
75 }
76 }
77
78 inline void OopsInKlassOrGenClosure::do_klass_barrier() {
79 assert(_scanned_klass != NULL, "Must be");
80 _scanned_klass->record_modified_oops();
81 }
82
83 // NOTE! Any changes made here should also be made
84 // in FastScanClosure::do_oop_work()
85 template <class T> inline void ScanClosure::do_oop_work(T* p) {
86 T heap_oop = oopDesc::load_heap_oop(p);
87 // Should we copy the obj?
88 if (!oopDesc::is_null(heap_oop)) {
89 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
90 if ((HeapWord*)obj < _boundary) {
91 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
92 oop new_obj = obj->is_forwarded() ? obj->forwardee()
93 : _g->copy_to_survivor_space(obj);
94 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
95 }
96
97 if (is_scanning_a_klass()) {
98 do_klass_barrier();
99 } else if (_gc_barrier) {
100 // Now call parent closure
101 do_barrier(p);
102 }
103 }
104 }
105
106 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); }
107 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
108
109 // NOTE! Any changes made here should also be made
110 // in ScanClosure::do_oop_work()
111 template <class T> inline void FastScanClosure::do_oop_work(T* p) {
112 T heap_oop = oopDesc::load_heap_oop(p);
113 // Should we copy the obj?
114 if (!oopDesc::is_null(heap_oop)) {
115 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
116 if ((HeapWord*)obj < _boundary) {
117 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
118 oop new_obj = obj->is_forwarded() ? obj->forwardee()
119 : _g->copy_to_survivor_space(obj);
120 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
121 if (is_scanning_a_klass()) {
122 do_klass_barrier();
123 } else if (_gc_barrier) {
124 // Now call parent closure
125 do_barrier(p);
126 }
127 }
128 }
129 }
130
131 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); }
132 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
133
134 // Note similarity to ScanClosure; the difference is that
135 // the barrier set is taken care of outside this closure.
136 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
137 assert(!oopDesc::is_null(*p), "null weak reference?");
138 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
139 // weak references are sometimes scanned twice; must check
140 // that to-space doesn't already contain this object
141 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
142 oop new_obj = obj->is_forwarded() ? obj->forwardee()
143 : _g->copy_to_survivor_space(obj);
144 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
145 }
146 }
147
148 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); }
149 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
150
151 #endif // SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP