1 /*
2 * Copyright (c) 2001, 2018, 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/generation.hpp"
33 #include "gc/shared/space.hpp"
34 #include "oops/oop.inline.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 _rs = GenCollectedHeap::heap()->rem_set();
47 }
48 }
49
50 template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
51 assert(generation()->is_in_reserved(p), "expected ref in generation");
52 T heap_oop = oopDesc::load_heap_oop(p);
53 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
54 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
55 // If p points to a younger generation, mark the card.
56 if ((HeapWord*)obj < _gen_boundary) {
57 _rs->inline_write_ref_field_gc(p, obj);
58 }
59 }
60
61 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
62 assert(generation()->is_in_reserved(p), "expected ref in generation");
63 T heap_oop = oopDesc::load_heap_oop(p);
64 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
65 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
66 // If p points to a younger generation, mark the card.
67 if ((HeapWord*)obj < gen_boundary()) {
68 rs()->write_ref_field_gc_par(p, obj);
69 }
70 }
71
72 inline void OopsInClassLoaderDataOrGenClosure::do_cld_barrier() {
73 assert(_scanned_cld != NULL, "Must be");
74 if (!_scanned_cld->has_modified_oops()) {
75 _scanned_cld->record_modified_oops();
76 }
77 }
78
79 // NOTE! Any changes made here should also be made
80 // in FastScanClosure::do_oop_work()
81 template <class T> inline void ScanClosure::do_oop_work(T* p) {
82 T heap_oop = oopDesc::load_heap_oop(p);
83 // Should we copy the obj?
84 if (!oopDesc::is_null(heap_oop)) {
85 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
86 if ((HeapWord*)obj < _boundary) {
87 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
88 oop new_obj = obj->is_forwarded() ? obj->forwardee()
89 : _g->copy_to_survivor_space(obj);
90 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
91 }
92
93 if (is_scanning_a_cld()) {
94 do_cld_barrier();
95 } else if (_gc_barrier) {
96 // Now call parent closure
97 do_barrier(p);
98 }
99 }
100 }
101
102 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); }
103 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
104
105 // NOTE! Any changes made here should also be made
106 // in ScanClosure::do_oop_work()
107 template <class T> inline void FastScanClosure::do_oop_work(T* p) {
108 T heap_oop = oopDesc::load_heap_oop(p);
109 // Should we copy the obj?
110 if (!oopDesc::is_null(heap_oop)) {
111 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
112 if ((HeapWord*)obj < _boundary) {
113 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
114 oop new_obj = obj->is_forwarded() ? obj->forwardee()
115 : _g->copy_to_survivor_space(obj);
116 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
117 if (is_scanning_a_cld()) {
118 do_cld_barrier();
119 } else if (_gc_barrier) {
120 // Now call parent closure
121 do_barrier(p);
122 }
123 }
124 }
125 }
126
127 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); }
128 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
129
130 template <class T> void FilteringClosure::do_oop_work(T* p) {
131 T heap_oop = oopDesc::load_heap_oop(p);
132 if (!oopDesc::is_null(heap_oop)) {
133 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
134 if ((HeapWord*)obj < _boundary) {
135 _cl->do_oop(p);
136 }
137 }
138 }
139
140 void FilteringClosure::do_oop_nv(oop* p) { FilteringClosure::do_oop_work(p); }
141 void FilteringClosure::do_oop_nv(narrowOop* p) { FilteringClosure::do_oop_work(p); }
142
143 // Note similarity to ScanClosure; the difference is that
144 // the barrier set is taken care of outside this closure.
145 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
146 assert(!oopDesc::is_null(*p), "null weak reference?");
147 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
148 // weak references are sometimes scanned twice; must check
149 // that to-space doesn't already contain this object
150 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
151 oop new_obj = obj->is_forwarded() ? obj->forwardee()
152 : _g->copy_to_survivor_space(obj);
153 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
154 }
155 }
156
157 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); }
158 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
159
160 #endif // SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP