1 /*
2 * Copyright (c) 2000, 2019, 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_GC_SHARED_MODREFBARRIERSET_HPP
26 #define SHARE_GC_SHARED_MODREFBARRIERSET_HPP
27
28 #include "gc/shared/barrierSet.hpp"
29 #include "memory/memRegion.hpp"
30
31 class Klass;
32
33 class ModRefBarrierSet: public BarrierSet {
34 protected:
35 ModRefBarrierSet(BarrierSetAssembler* barrier_set_assembler,
36 BarrierSetC1* barrier_set_c1,
37 BarrierSetC2* barrier_set_c2,
38 const BarrierSet::FakeRtti& fake_rtti)
39 : BarrierSet(barrier_set_assembler,
40 barrier_set_c1,
41 barrier_set_c2,
42 NULL /* barrier_set_nmethod */,
43 fake_rtti.add_tag(BarrierSet::ModRef)) { }
44 ~ModRefBarrierSet() { }
45
46 public:
47 template <DecoratorSet decorators, typename T>
48 inline void write_ref_field_pre(T* addr) {}
49
50 template <DecoratorSet decorators, typename T>
51 inline void write_ref_field_post(T *addr, oop new_value) {}
52
53 // Causes all refs in "mr" to be assumed to be modified.
54 virtual void invalidate(MemRegion mr) = 0;
55 virtual void write_region(MemRegion mr) = 0;
56
57 // Operations on arrays, or general regions (e.g., for "clone") may be
58 // optimized by some barriers.
59
60 // Below length is the # array elements being written
61 virtual void write_ref_array_pre(oop* dst, size_t length,
62 bool dest_uninitialized = false) {}
63 virtual void write_ref_array_pre(narrowOop* dst, size_t length,
64 bool dest_uninitialized = false) {}
65 // Below count is the # array elements being written, starting
66 // at the address "start", which may not necessarily be HeapWord-aligned
67 inline void write_ref_array(HeapWord* start, size_t count);
68
69 protected:
70 virtual void write_ref_array_work(MemRegion mr) = 0;
71 public:
72 // The ModRef abstraction introduces pre and post barriers
73 template <DecoratorSet decorators, typename BarrierSetT>
74 class AccessBarrier: public BarrierSet::AccessBarrier<decorators, BarrierSetT> {
75 typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;
76
77 public:
78 template <typename T>
79 static void oop_store_in_heap(T* addr, oop value);
80 template <typename T>
81 static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value);
82 template <typename T>
83 static oop oop_atomic_xchg_in_heap(oop new_value, T* addr);
84
85 template <typename T>
86 static void oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
87 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
88 size_t length);
89 private:
90 // Failing checkcast or check null during copy, still needs barrier
91 template <typename T>
92 static inline void oop_arraycopy_partial_barrier(BarrierSetT *bs, T* dst_raw, T* p);
93 public:
94 static void clone_in_heap(oop src, oop dst, size_t size);
95
96 static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
97 oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value);
98 }
99
100 static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
101 return oop_atomic_xchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset));
102 }
103
104 static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
105 return oop_atomic_cmpxchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset), compare_value);
106 }
107 };
108 };
109
110 template<>
111 struct BarrierSet::GetName<ModRefBarrierSet> {
112 static const BarrierSet::Name value = BarrierSet::ModRef;
113 };
114
115 #endif // SHARE_GC_SHARED_MODREFBARRIERSET_HPP