1/*
2 * Copyright (c) 2001, 2016, 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
35inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :
36  ExtendedOopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) {
37  set_generation(gen);
38}
39
40inline void OopsInGenClosure::set_generation(Generation* gen) {
41  _gen = gen;
42  _gen_boundary = _gen->reserved().start();
43  // Barrier set for the heap, must be set after heap is initialized
44  if (_rs == NULL) {
45    _rs = GenCollectedHeap::heap()->rem_set();
46  }
47}
48
49template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
50  assert(generation()->is_in_reserved(p), "expected ref in generation");
51  T heap_oop = oopDesc::load_heap_oop(p);
52  assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
53  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
54  // If p points to a younger generation, mark the card.
55  if ((HeapWord*)obj < _gen_boundary) {
56    _rs->inline_write_ref_field_gc(p, obj);
57  }
58}
59
60template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
61  assert(generation()->is_in_reserved(p), "expected ref in generation");
62  T heap_oop = oopDesc::load_heap_oop(p);
63  assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
64  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
65  // If p points to a younger generation, mark the card.
66  if ((HeapWord*)obj < gen_boundary()) {
67    rs()->write_ref_field_gc_par(p, obj);
68  }
69}
70
71inline void OopsInKlassOrGenClosure::do_klass_barrier() {
72  assert(_scanned_klass != NULL, "Must be");
73  _scanned_klass->record_modified_oops();
74}
75
76// NOTE! Any changes made here should also be made
77// in FastScanClosure::do_oop_work()
78template <class T> inline void ScanClosure::do_oop_work(T* p) {
79  T heap_oop = oopDesc::load_heap_oop(p);
80  // Should we copy the obj?
81  if (!oopDesc::is_null(heap_oop)) {
82    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
83    if ((HeapWord*)obj < _boundary) {
84      assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
85      oop new_obj = obj->is_forwarded() ? obj->forwardee()
86                                        : _g->copy_to_survivor_space(obj);
87      oopDesc::encode_store_heap_oop_not_null(p, new_obj);
88    }
89
90    if (is_scanning_a_klass()) {
91      do_klass_barrier();
92    } else if (_gc_barrier) {
93      // Now call parent closure
94      do_barrier(p);
95    }
96  }
97}
98
99inline void ScanClosure::do_oop_nv(oop* p)       { ScanClosure::do_oop_work(p); }
100inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
101
102// NOTE! Any changes made here should also be made
103// in ScanClosure::do_oop_work()
104template <class T> inline void FastScanClosure::do_oop_work(T* p) {
105  T heap_oop = oopDesc::load_heap_oop(p);
106  // Should we copy the obj?
107  if (!oopDesc::is_null(heap_oop)) {
108    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
109    if ((HeapWord*)obj < _boundary) {
110      assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
111      oop new_obj = obj->is_forwarded() ? obj->forwardee()
112                                        : _g->copy_to_survivor_space(obj);
113      oopDesc::encode_store_heap_oop_not_null(p, new_obj);
114      if (is_scanning_a_klass()) {
115        do_klass_barrier();
116      } else if (_gc_barrier) {
117        // Now call parent closure
118        do_barrier(p);
119      }
120    }
121  }
122}
123
124inline void FastScanClosure::do_oop_nv(oop* p)       { FastScanClosure::do_oop_work(p); }
125inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
126
127template <class T> void FilteringClosure::do_oop_work(T* p) {
128  T heap_oop = oopDesc::load_heap_oop(p);
129  if (!oopDesc::is_null(heap_oop)) {
130    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
131    if ((HeapWord*)obj < _boundary) {
132      _cl->do_oop(p);
133    }
134  }
135}
136
137void FilteringClosure::do_oop_nv(oop* p)       { FilteringClosure::do_oop_work(p); }
138void FilteringClosure::do_oop_nv(narrowOop* p) { FilteringClosure::do_oop_work(p); }
139
140// Note similarity to ScanClosure; the difference is that
141// the barrier set is taken care of outside this closure.
142template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
143  assert(!oopDesc::is_null(*p), "null weak reference?");
144  oop obj = oopDesc::load_decode_heap_oop_not_null(p);
145  // weak references are sometimes scanned twice; must check
146  // that to-space doesn't already contain this object
147  if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
148    oop new_obj = obj->is_forwarded() ? obj->forwardee()
149                                      : _g->copy_to_survivor_space(obj);
150    oopDesc::encode_store_heap_oop_not_null(p, new_obj);
151  }
152}
153
154inline void ScanWeakRefClosure::do_oop_nv(oop* p)       { ScanWeakRefClosure::do_oop_work(p); }
155inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
156
157#endif // SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP
158