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_G1_G1BARRIERSET_HPP
26 #define SHARE_VM_GC_G1_G1BARRIERSET_HPP
27
28 #include "gc/shared/cardTableModRefBS.hpp"
29
30 class DirtyCardQueueSet;
31 class CardTable;
32 class G1CardTable;
33
34 // This barrier is specialized to use a logging barrier to support
35 // snapshot-at-the-beginning marking.
36
37 class G1BarrierSet: public CardTableModRefBS {
38 friend class VMStructs;
39 private:
40 DirtyCardQueueSet& _dcqs;
41
42 public:
43 G1BarrierSet(G1CardTable* table);
44 ~G1BarrierSet() { }
45
46 // Add "pre_val" to a set of objects that may have been disconnected from the
47 // pre-marking object graph.
48 static void enqueue(oop pre_val);
49
50 static void enqueue_if_weak_or_archive(DecoratorSet decorators, oop value);
51
52 template <class T> void write_ref_array_pre_work(T* dst, int count);
53 virtual void write_ref_array_pre(oop* dst, int count, bool dest_uninitialized);
54 virtual void write_ref_array_pre(narrowOop* dst, int count, bool dest_uninitialized);
55
56 template <DecoratorSet decorators, typename T>
57 void write_ref_field_pre(T* field);
58
59 // NB: if you do a whole-heap invalidation, the "usual invariant" defined
60 // above no longer applies.
61 void invalidate(MemRegion mr);
62
63 void write_region(MemRegion mr) { invalidate(mr); }
64 void write_ref_array_work(MemRegion mr) { invalidate(mr); }
65
66 template <DecoratorSet decorators, typename T>
67 void write_ref_field_post(T* field, oop new_val);
68 void write_ref_field_post_slow(volatile jbyte* byte);
69
70 virtual void on_thread_attach(JavaThread* thread);
71 virtual void on_thread_detach(JavaThread* thread);
72
73 // Callbacks for runtime accesses.
74 template <DecoratorSet decorators, typename BarrierSetT = G1BarrierSet>
75 class AccessBarrier: public ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> {
76 typedef ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> ModRef;
77 typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;
78
79 public:
80 // Needed for loads on non-heap weak references
81 template <typename T>
82 static oop oop_load_not_in_heap(T* addr);
83
84 // Needed for non-heap stores
85 template <typename T>
86 static void oop_store_not_in_heap(T* addr, oop new_value);
87
88 // Needed for weak references
89 static oop oop_load_in_heap_at(oop base, ptrdiff_t offset);
90
91 // Defensive: will catch weak oops at addresses in heap
92 template <typename T>
93 static oop oop_load_in_heap(T* addr);
94 };
95 };
96
97 template<>
98 struct BarrierSet::GetName<G1BarrierSet> {
99 static const BarrierSet::Name value = BarrierSet::G1BarrierSet;
100 };
101
102 template<>
103 struct BarrierSet::GetType<BarrierSet::G1BarrierSet> {
104 typedef ::G1BarrierSet type;
105 };
106
107 #endif // SHARE_VM_GC_G1_G1BARRIERSET_HPP