1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_WasiAtomic_h
#define mozilla_WasiAtomic_h
// Clang >= 14 supports <atomic> for wasm targets.
#if _LIBCPP_VERSION >= 14000
# include <atomic>
#else
# include <cstdint>
// WASI doesn't support <atomic> and we use it as single-threaded for now.
// This is a stub implementation of std atomics to build WASI port of SM.
namespace std {
enum memory_order {
relaxed,
consume, // load-consume
acquire, // load-acquire
release, // store-release
acq_rel, // store-release load-acquire
seq_cst // store-release load-acquire
};
inline constexpr auto memory_order_relaxed = memory_order::relaxed;
inline constexpr auto memory_order_consume = memory_order::consume;
inline constexpr auto memory_order_acquire = memory_order::acquire;
inline constexpr auto memory_order_release = memory_order::release;
inline constexpr auto memory_order_acq_rel = memory_order::acq_rel;
inline constexpr auto memory_order_seq_cst = memory_order::seq_cst;
template <class T>
struct atomic {
using value_type = T;
value_type value_;
atomic() noexcept = default;
constexpr atomic(T desired) noexcept : value_{desired} {}
atomic(const atomic&) = delete;
atomic& operator=(const atomic&) = delete;
atomic& operator=(const atomic&) volatile = delete;
~atomic() noexcept = default;
T load(memory_order m = memory_order_seq_cst) const volatile noexcept {
return value_;
}
void store(T desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
value_ = desired;
}
T operator=(T desired) volatile noexcept { return value_ = desired; }
T exchange(T desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
T tmp = value_;
value_ = desired;
return tmp;
}
bool compare_exchange_weak(T& expected, T desired, memory_order,
memory_order) volatile noexcept {
expected = desired;
return true;
}
bool compare_exchange_weak(
T& expected, T desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
expected = desired;
return true;
}
bool compare_exchange_strong(T& expected, T desired, memory_order,
memory_order) volatile noexcept {
expected = desired;
return true;
}
bool compare_exchange_strong(
T& expected, T desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
expected = desired;
return true;
}
T fetch_add(T arg, memory_order m = memory_order_seq_cst) volatile noexcept {
T previous = value_;
value_ = value_ + arg;
return previous;
}
T fetch_sub(T arg, memory_order m = memory_order_seq_cst) volatile noexcept {
T previous = value_;
value_ = value_ - arg;
return previous;
}
T fetch_or(T arg, memory_order m = memory_order_seq_cst) volatile noexcept {
T previous = value_;
value_ = value_ | arg;
return previous;
}
T fetch_xor(T arg, memory_order m = memory_order_seq_cst) volatile noexcept {
T previous = value_;
value_ = value_ ^ arg;
return previous;
}
T fetch_and(T arg, memory_order m = memory_order_seq_cst) volatile noexcept {
T previous = value_;
value_ = value_ & arg;
return previous;
}
};
template <class T>
struct atomic<T*> {
using value_type = T*;
using difference_type = ptrdiff_t;
value_type value_;
atomic() noexcept = default;
constexpr atomic(T* desired) noexcept : value_{desired} {}
atomic(const atomic&) = delete;
atomic& operator=(const atomic&) = delete;
atomic& operator=(const atomic&) volatile = delete;
T* load(memory_order m = memory_order_seq_cst) const volatile noexcept {
return value_;
}
void store(T* desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
value_ = desired;
}
T* operator=(T* other) volatile noexcept { return value_ = other; }
T* exchange(T* desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
T* previous = value_;
value_ = desired;
return previous;
}
bool compare_exchange_weak(T*& expected, T* desired, memory_order s,
memory_order f) volatile noexcept {
expected = desired;
return true;
}
bool compare_exchange_weak(
T*& expected, T* desired,
memory_order m = memory_order_seq_cst) volatile noexcept {
expected = desired;
return true;
}
bool compare_exchange_strong(T*& expected, T* desired, memory_order s,
memory_order f) volatile noexcept {
expected = desired;
return true;
}
T* fetch_add(ptrdiff_t arg,
memory_order m = memory_order_seq_cst) volatile noexcept {
T* previous = value_;
value_ = value_ + arg;
return previous;
}
T* fetch_sub(ptrdiff_t arg,
memory_order m = memory_order_seq_cst) volatile noexcept {
T* previous = value_;
value_ = value_ - arg;
return previous;
}
};
using atomic_uint8_t = atomic<uint8_t>;
using atomic_uint16_t = atomic<uint16_t>;
using atomic_uint32_t = atomic<uint32_t>;
using atomic_uint64_t = atomic<uint64_t>;
} // namespace std
#endif
#endif // mozilla_WasiAtomic_h
|
