1 /*
2 * Copyright (c) 2001, 2014, 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
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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/space.hpp"
35
36 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :
37 ExtendedOopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) {
38 set_generation(gen);
39 }
40
41 inline void OopsInGenClosure::set_generation(Generation* gen) {
42 _gen = gen;
43 _gen_boundary = _gen->reserved().start();
44 // Barrier set for the heap, must be set after heap is initialized
45 if (_rs == NULL) {
46 GenRemSet* rs = GenCollectedHeap::heap()->rem_set();
47 _rs = (CardTableRS*)rs;
48 }
49 }
50
51 template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
52 assert(generation()->is_in_reserved(p), "expected ref in generation");
53 T heap_oop = oopDesc::load_heap_oop(p);
54 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
55 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
56 // If p points to a younger generation, mark the card.
57 if ((HeapWord*)obj < _gen_boundary) {
58 _rs->inline_write_ref_field_gc(p, obj);
59 }
60 }
61
62 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
63 assert(generation()->is_in_reserved(p), "expected ref in generation");
64 T heap_oop = oopDesc::load_heap_oop(p);
65 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
66 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
67 // If p points to a younger generation, mark the card.
68 if ((HeapWord*)obj < gen_boundary()) {
69 rs()->write_ref_field_gc_par(p, obj);
70 }
71 }
72
73 inline void OopsInKlassOrGenClosure::do_klass_barrier() {
74 assert(_scanned_klass != NULL, "Must be");
75 _scanned_klass->record_modified_oops();
76 }
77
78 // NOTE! Any changes made here should also be made
79 // in FastScanClosure::do_oop_work()
80 template <class T> inline void ScanClosure::do_oop_work(T* p) {
81 T heap_oop = oopDesc::load_heap_oop(p);
82 // Should we copy the obj?
83 if (!oopDesc::is_null(heap_oop)) {
84 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
85 if ((HeapWord*)obj < _boundary) {
86 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
87 oop new_obj = obj->is_forwarded() ? obj->forwardee()
88 : _g->copy_to_survivor_space(obj);
89 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
90 }
91
92 if (is_scanning_a_klass()) {
93 do_klass_barrier();
94 } else if (_gc_barrier) {
95 // Now call parent closure
96 do_barrier(p);
97 }
98 }
99 }
100
101 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); }
102 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
103
104 // NOTE! Any changes made here should also be made
105 // in ScanClosure::do_oop_work()
106 template <class T> inline void FastScanClosure::do_oop_work(T* p) {
107 T heap_oop = oopDesc::load_heap_oop(p);
108 // Should we copy the obj?
109 if (!oopDesc::is_null(heap_oop)) {
110 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
111 if ((HeapWord*)obj < _boundary) {
112 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
113 oop new_obj = obj->is_forwarded() ? obj->forwardee()
114 : _g->copy_to_survivor_space(obj);
115 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
116 if (is_scanning_a_klass()) {
117 do_klass_barrier();
118 } else if (_gc_barrier) {
119 // Now call parent closure
120 do_barrier(p);
121 }
122 }
123 }
124 }
125
126 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); }
127 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
128
129 // Note similarity to ScanClosure; the difference is that
130 // the barrier set is taken care of outside this closure.
131 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
132 assert(!oopDesc::is_null(*p), "null weak reference?");
133 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
134 // weak references are sometimes scanned twice; must check
135 // that to-space doesn't already contain this object
136 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
137 oop new_obj = obj->is_forwarded() ? obj->forwardee()
138 : _g->copy_to_survivor_space(obj);
139 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
140 }
141 }
142
143 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); }
144 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
145
146 #endif // SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP