1/*===---- stdatomic.h - Standard header for atomic types and operations -----===
2 *
3 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 * See https://llvm.org/LICENSE.txt for license information.
5 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 *
7 *===-----------------------------------------------------------------------===
8 */
9
10#ifndef __CLANG_STDATOMIC_H
11#define __CLANG_STDATOMIC_H
12
13/* If we're hosted, fall back to the system's stdatomic.h. FreeBSD, for
14 * example, already has a Clang-compatible stdatomic.h header.
15 *
16 * Exclude the MSVC path as well as the MSVC header as of the 14.31.30818
17 * explicitly disallows `stdatomic.h` in the C mode via an `#error`.  Fallback
18 * to the clang resource header until that is fully supported.  The
19 * `stdatomic.h` header requires C++ 23 or newer.
20 */
21#if __STDC_HOSTED__ &&                                                         \
22    __has_include_next(<stdatomic.h>) &&                                       \
23    (!defined(_MSC_VER) || (defined(__cplusplus) && __cplusplus >= 202002L))
24# include_next <stdatomic.h>
25#else
26
27#include <stddef.h>
28#include <stdint.h>
29
30#ifdef __cplusplus
31extern "C" {
32#endif
33
34/* 7.17.1 Introduction */
35
36#define ATOMIC_BOOL_LOCK_FREE       __CLANG_ATOMIC_BOOL_LOCK_FREE
37#define ATOMIC_CHAR_LOCK_FREE       __CLANG_ATOMIC_CHAR_LOCK_FREE
38#define ATOMIC_CHAR16_T_LOCK_FREE   __CLANG_ATOMIC_CHAR16_T_LOCK_FREE
39#define ATOMIC_CHAR32_T_LOCK_FREE   __CLANG_ATOMIC_CHAR32_T_LOCK_FREE
40#define ATOMIC_WCHAR_T_LOCK_FREE    __CLANG_ATOMIC_WCHAR_T_LOCK_FREE
41#define ATOMIC_SHORT_LOCK_FREE      __CLANG_ATOMIC_SHORT_LOCK_FREE
42#define ATOMIC_INT_LOCK_FREE        __CLANG_ATOMIC_INT_LOCK_FREE
43#define ATOMIC_LONG_LOCK_FREE       __CLANG_ATOMIC_LONG_LOCK_FREE
44#define ATOMIC_LLONG_LOCK_FREE      __CLANG_ATOMIC_LLONG_LOCK_FREE
45#define ATOMIC_POINTER_LOCK_FREE    __CLANG_ATOMIC_POINTER_LOCK_FREE
46
47/* 7.17.2 Initialization */
48
49#define ATOMIC_VAR_INIT(value) (value)
50#if ((defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201710L) ||             \
51     (defined(__cplusplus) && __cplusplus >= 202002L)) &&                      \
52    !defined(_CLANG_DISABLE_CRT_DEPRECATION_WARNINGS)
53/* ATOMIC_VAR_INIT was deprecated in C17 and C++20. */
54#pragma clang deprecated(ATOMIC_VAR_INIT)
55#endif
56#define atomic_init __c11_atomic_init
57
58/* 7.17.3 Order and consistency */
59
60typedef enum memory_order {
61  memory_order_relaxed = __ATOMIC_RELAXED,
62  memory_order_consume = __ATOMIC_CONSUME,
63  memory_order_acquire = __ATOMIC_ACQUIRE,
64  memory_order_release = __ATOMIC_RELEASE,
65  memory_order_acq_rel = __ATOMIC_ACQ_REL,
66  memory_order_seq_cst = __ATOMIC_SEQ_CST
67} memory_order;
68
69#define kill_dependency(y) (y)
70
71/* 7.17.4 Fences */
72
73/* These should be provided by the libc implementation. */
74void atomic_thread_fence(memory_order);
75void atomic_signal_fence(memory_order);
76
77#define atomic_thread_fence(order) __c11_atomic_thread_fence(order)
78#define atomic_signal_fence(order) __c11_atomic_signal_fence(order)
79
80/* 7.17.5 Lock-free property */
81
82#define atomic_is_lock_free(obj) __c11_atomic_is_lock_free(sizeof(*(obj)))
83
84/* 7.17.6 Atomic integer types */
85
86#ifdef __cplusplus
87typedef _Atomic(bool)               atomic_bool;
88#else
89typedef _Atomic(_Bool)              atomic_bool;
90#endif
91typedef _Atomic(char)               atomic_char;
92typedef _Atomic(signed char)        atomic_schar;
93typedef _Atomic(unsigned char)      atomic_uchar;
94typedef _Atomic(short)              atomic_short;
95typedef _Atomic(unsigned short)     atomic_ushort;
96typedef _Atomic(int)                atomic_int;
97typedef _Atomic(unsigned int)       atomic_uint;
98typedef _Atomic(long)               atomic_long;
99typedef _Atomic(unsigned long)      atomic_ulong;
100typedef _Atomic(long long)          atomic_llong;
101typedef _Atomic(unsigned long long) atomic_ullong;
102typedef _Atomic(uint_least16_t)     atomic_char16_t;
103typedef _Atomic(uint_least32_t)     atomic_char32_t;
104typedef _Atomic(wchar_t)            atomic_wchar_t;
105typedef _Atomic(int_least8_t)       atomic_int_least8_t;
106typedef _Atomic(uint_least8_t)      atomic_uint_least8_t;
107typedef _Atomic(int_least16_t)      atomic_int_least16_t;
108typedef _Atomic(uint_least16_t)     atomic_uint_least16_t;
109typedef _Atomic(int_least32_t)      atomic_int_least32_t;
110typedef _Atomic(uint_least32_t)     atomic_uint_least32_t;
111typedef _Atomic(int_least64_t)      atomic_int_least64_t;
112typedef _Atomic(uint_least64_t)     atomic_uint_least64_t;
113typedef _Atomic(int_fast8_t)        atomic_int_fast8_t;
114typedef _Atomic(uint_fast8_t)       atomic_uint_fast8_t;
115typedef _Atomic(int_fast16_t)       atomic_int_fast16_t;
116typedef _Atomic(uint_fast16_t)      atomic_uint_fast16_t;
117typedef _Atomic(int_fast32_t)       atomic_int_fast32_t;
118typedef _Atomic(uint_fast32_t)      atomic_uint_fast32_t;
119typedef _Atomic(int_fast64_t)       atomic_int_fast64_t;
120typedef _Atomic(uint_fast64_t)      atomic_uint_fast64_t;
121typedef _Atomic(intptr_t)           atomic_intptr_t;
122typedef _Atomic(uintptr_t)          atomic_uintptr_t;
123typedef _Atomic(size_t)             atomic_size_t;
124typedef _Atomic(ptrdiff_t)          atomic_ptrdiff_t;
125typedef _Atomic(intmax_t)           atomic_intmax_t;
126typedef _Atomic(uintmax_t)          atomic_uintmax_t;
127
128/* 7.17.7 Operations on atomic types */
129
130#define atomic_store(object, desired) __c11_atomic_store(object, desired, __ATOMIC_SEQ_CST)
131#define atomic_store_explicit __c11_atomic_store
132
133#define atomic_load(object) __c11_atomic_load(object, __ATOMIC_SEQ_CST)
134#define atomic_load_explicit __c11_atomic_load
135
136#define atomic_exchange(object, desired) __c11_atomic_exchange(object, desired, __ATOMIC_SEQ_CST)
137#define atomic_exchange_explicit __c11_atomic_exchange
138
139#define atomic_compare_exchange_strong(object, expected, desired) __c11_atomic_compare_exchange_strong(object, expected, desired, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)
140#define atomic_compare_exchange_strong_explicit __c11_atomic_compare_exchange_strong
141
142#define atomic_compare_exchange_weak(object, expected, desired) __c11_atomic_compare_exchange_weak(object, expected, desired, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)
143#define atomic_compare_exchange_weak_explicit __c11_atomic_compare_exchange_weak
144
145#define atomic_fetch_add(object, operand) __c11_atomic_fetch_add(object, operand, __ATOMIC_SEQ_CST)
146#define atomic_fetch_add_explicit __c11_atomic_fetch_add
147
148#define atomic_fetch_sub(object, operand) __c11_atomic_fetch_sub(object, operand, __ATOMIC_SEQ_CST)
149#define atomic_fetch_sub_explicit __c11_atomic_fetch_sub
150
151#define atomic_fetch_or(object, operand) __c11_atomic_fetch_or(object, operand, __ATOMIC_SEQ_CST)
152#define atomic_fetch_or_explicit __c11_atomic_fetch_or
153
154#define atomic_fetch_xor(object, operand) __c11_atomic_fetch_xor(object, operand, __ATOMIC_SEQ_CST)
155#define atomic_fetch_xor_explicit __c11_atomic_fetch_xor
156
157#define atomic_fetch_and(object, operand) __c11_atomic_fetch_and(object, operand, __ATOMIC_SEQ_CST)
158#define atomic_fetch_and_explicit __c11_atomic_fetch_and
159
160/* 7.17.8 Atomic flag type and operations */
161
162typedef struct atomic_flag { atomic_bool _Value; } atomic_flag;
163
164#define ATOMIC_FLAG_INIT { 0 }
165
166/* These should be provided by the libc implementation. */
167#ifdef __cplusplus
168bool atomic_flag_test_and_set(volatile atomic_flag *);
169bool atomic_flag_test_and_set_explicit(volatile atomic_flag *, memory_order);
170#else
171_Bool atomic_flag_test_and_set(volatile atomic_flag *);
172_Bool atomic_flag_test_and_set_explicit(volatile atomic_flag *, memory_order);
173#endif
174void atomic_flag_clear(volatile atomic_flag *);
175void atomic_flag_clear_explicit(volatile atomic_flag *, memory_order);
176
177#define atomic_flag_test_and_set(object) __c11_atomic_exchange(&(object)->_Value, 1, __ATOMIC_SEQ_CST)
178#define atomic_flag_test_and_set_explicit(object, order) __c11_atomic_exchange(&(object)->_Value, 1, order)
179
180#define atomic_flag_clear(object) __c11_atomic_store(&(object)->_Value, 0, __ATOMIC_SEQ_CST)
181#define atomic_flag_clear_explicit(object, order) __c11_atomic_store(&(object)->_Value, 0, order)
182
183#ifdef __cplusplus
184}
185#endif
186
187#endif /* __STDC_HOSTED__ */
188#endif /* __CLANG_STDATOMIC_H */
189
190