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/cardTableBarrierSet.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 CardTableBarrierSet {
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, size_t count);
53 virtual void write_ref_array_pre(oop* dst, size_t count, bool dest_uninitialized);
54 virtual void write_ref_array_pre(narrowOop* dst, size_t count, bool dest_uninitialized);
55
56 static void write_ref_array_pre_oop_entry(oop* dst, size_t length);
57 static void write_ref_array_pre_narrow_oop_entry(narrowOop* dst, size_t length);
58 static void write_ref_array_post_entry(HeapWord* dst, size_t length);
59
60 template <DecoratorSet decorators, typename T>
61 void write_ref_field_pre(T* field);
62
63 // NB: if you do a whole-heap invalidation, the "usual invariant" defined
64 // above no longer applies.
65 void invalidate(MemRegion mr);
66
67 void write_region(MemRegion mr) { invalidate(mr); }
68 void write_ref_array_work(MemRegion mr) { invalidate(mr); }
69
70 template <DecoratorSet decorators, typename T>
71 void write_ref_field_post(T* field, oop new_val);
72 void write_ref_field_post_slow(volatile jbyte* byte);
73
74 virtual void on_thread_attach(JavaThread* thread);
75 virtual void on_thread_detach(JavaThread* thread);
76
77 // Callbacks for runtime accesses.
78 template <DecoratorSet decorators, typename BarrierSetT = G1BarrierSet>
79 class AccessBarrier: public ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> {
80 typedef ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> ModRef;
81 typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;
82
83 public:
84 // Needed for loads on non-heap weak references
85 template <typename T>
86 static oop oop_load_not_in_heap(T* addr);
87
88 // Needed for non-heap stores
89 template <typename T>
90 static void oop_store_not_in_heap(T* addr, oop new_value);
91
92 // Needed for weak references
93 static oop oop_load_in_heap_at(oop base, ptrdiff_t offset);
94
95 // Defensive: will catch weak oops at addresses in heap
96 template <typename T>
97 static oop oop_load_in_heap(T* addr);
98 };
99 };
100
101 template<>
102 struct BarrierSet::GetName<G1BarrierSet> {
103 static const BarrierSet::Name value = BarrierSet::G1BarrierSet;
104 };
105
106 template<>
107 struct BarrierSet::GetType<BarrierSet::G1BarrierSet> {
108 typedef ::G1BarrierSet type;
109 };
110
111 #endif // SHARE_VM_GC_G1_G1BARRIERSET_HPP