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#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
39#define ATOMIC_CHAR8_T_LOCK_FREE __CLANG_ATOMIC_CHAR8_T_LOCK_FREE
40#endif
41#define ATOMIC_CHAR16_T_LOCK_FREE __CLANG_ATOMIC_CHAR16_T_LOCK_FREE
42#define ATOMIC_CHAR32_T_LOCK_FREE __CLANG_ATOMIC_CHAR32_T_LOCK_FREE
43#define ATOMIC_WCHAR_T_LOCK_FREE __CLANG_ATOMIC_WCHAR_T_LOCK_FREE
44#define ATOMIC_SHORT_LOCK_FREE __CLANG_ATOMIC_SHORT_LOCK_FREE
45#define ATOMIC_INT_LOCK_FREE __CLANG_ATOMIC_INT_LOCK_FREE
46#define ATOMIC_LONG_LOCK_FREE __CLANG_ATOMIC_LONG_LOCK_FREE
47#define ATOMIC_LLONG_LOCK_FREE __CLANG_ATOMIC_LLONG_LOCK_FREE
48#define ATOMIC_POINTER_LOCK_FREE __CLANG_ATOMIC_POINTER_LOCK_FREE
49
50/* 7.17.2 Initialization */
51#if (defined(__STDC_VERSION__) && __STDC_VERSION__ < 202311L) || \
52 defined(__cplusplus)
53/* ATOMIC_VAR_INIT was removed in C23, but still remains in C++23. */
54#define ATOMIC_VAR_INIT(value) (value)
55#endif
56
57#if ((defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201710L && \
58 __STDC_VERSION__ < 202311L) || \
59 (defined(__cplusplus) && __cplusplus >= 202002L)) && \
60 !defined(_CLANG_DISABLE_CRT_DEPRECATION_WARNINGS)
61/* ATOMIC_VAR_INIT was deprecated in C17 and C++20. */
62#pragma clang deprecated(ATOMIC_VAR_INIT)
63#endif
64#define atomic_init __c11_atomic_init
65
66/* 7.17.3 Order and consistency */
67
68typedef enum memory_order {
69 memory_order_relaxed = __ATOMIC_RELAXED,
70 memory_order_consume = __ATOMIC_CONSUME,
71 memory_order_acquire = __ATOMIC_ACQUIRE,
72 memory_order_release = __ATOMIC_RELEASE,
73 memory_order_acq_rel = __ATOMIC_ACQ_REL,
74 memory_order_seq_cst = __ATOMIC_SEQ_CST
75} memory_order;
76
77#define kill_dependency(y) (y)
78
79/* 7.17.4 Fences */
80
81/* These should be provided by the libc implementation. */
82void atomic_thread_fence(memory_order);
83void atomic_signal_fence(memory_order);
84
85#define atomic_thread_fence(order) __c11_atomic_thread_fence(order)
86#define atomic_signal_fence(order) __c11_atomic_signal_fence(order)
87
88/* 7.17.5 Lock-free property */
89
90#define atomic_is_lock_free(obj) __c11_atomic_is_lock_free(sizeof(*(obj)))
91
92/* 7.17.6 Atomic integer types */
93
94#ifdef __cplusplus
95typedef _Atomic(bool) atomic_bool;
96#else
97typedef _Atomic(_Bool) atomic_bool;
98#endif
99typedef _Atomic(char) atomic_char;
100typedef _Atomic(signed char) atomic_schar;
101typedef _Atomic(unsigned char) atomic_uchar;
102typedef _Atomic(short) atomic_short;
103typedef _Atomic(unsigned short) atomic_ushort;
104typedef _Atomic(int) atomic_int;
105typedef _Atomic(unsigned int) atomic_uint;
106typedef _Atomic(long) atomic_long;
107typedef _Atomic(unsigned long) atomic_ulong;
108typedef _Atomic(long long) atomic_llong;
109typedef _Atomic(unsigned long long) atomic_ullong;
110#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
111typedef _Atomic(unsigned char) atomic_char8_t;
112#endif
113typedef _Atomic(uint_least16_t) atomic_char16_t;
114typedef _Atomic(uint_least32_t) atomic_char32_t;
115typedef _Atomic(wchar_t) atomic_wchar_t;
116typedef _Atomic(int_least8_t) atomic_int_least8_t;
117typedef _Atomic(uint_least8_t) atomic_uint_least8_t;
118typedef _Atomic(int_least16_t) atomic_int_least16_t;
119typedef _Atomic(uint_least16_t) atomic_uint_least16_t;
120typedef _Atomic(int_least32_t) atomic_int_least32_t;
121typedef _Atomic(uint_least32_t) atomic_uint_least32_t;
122typedef _Atomic(int_least64_t) atomic_int_least64_t;
123typedef _Atomic(uint_least64_t) atomic_uint_least64_t;
124typedef _Atomic(int_fast8_t) atomic_int_fast8_t;
125typedef _Atomic(uint_fast8_t) atomic_uint_fast8_t;
126typedef _Atomic(int_fast16_t) atomic_int_fast16_t;
127typedef _Atomic(uint_fast16_t) atomic_uint_fast16_t;
128typedef _Atomic(int_fast32_t) atomic_int_fast32_t;
129typedef _Atomic(uint_fast32_t) atomic_uint_fast32_t;
130typedef _Atomic(int_fast64_t) atomic_int_fast64_t;
131typedef _Atomic(uint_fast64_t) atomic_uint_fast64_t;
132typedef _Atomic(intptr_t) atomic_intptr_t;
133typedef _Atomic(uintptr_t) atomic_uintptr_t;
134typedef _Atomic(size_t) atomic_size_t;
135typedef _Atomic(ptrdiff_t) atomic_ptrdiff_t;
136typedef _Atomic(intmax_t) atomic_intmax_t;
137typedef _Atomic(uintmax_t) atomic_uintmax_t;
138
139/* 7.17.7 Operations on atomic types */
140
141#define atomic_store(object, desired) __c11_atomic_store(object, desired, __ATOMIC_SEQ_CST)
142#define atomic_store_explicit __c11_atomic_store
143
144#define atomic_load(object) __c11_atomic_load(object, __ATOMIC_SEQ_CST)
145#define atomic_load_explicit __c11_atomic_load
146
147#define atomic_exchange(object, desired) __c11_atomic_exchange(object, desired, __ATOMIC_SEQ_CST)
148#define atomic_exchange_explicit __c11_atomic_exchange
149
150#define atomic_compare_exchange_strong(object, expected, desired) __c11_atomic_compare_exchange_strong(object, expected, desired, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)
151#define atomic_compare_exchange_strong_explicit __c11_atomic_compare_exchange_strong
152
153#define atomic_compare_exchange_weak(object, expected, desired) __c11_atomic_compare_exchange_weak(object, expected, desired, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)
154#define atomic_compare_exchange_weak_explicit __c11_atomic_compare_exchange_weak
155
156#define atomic_fetch_add(object, operand) __c11_atomic_fetch_add(object, operand, __ATOMIC_SEQ_CST)
157#define atomic_fetch_add_explicit __c11_atomic_fetch_add
158
159#define atomic_fetch_sub(object, operand) __c11_atomic_fetch_sub(object, operand, __ATOMIC_SEQ_CST)
160#define atomic_fetch_sub_explicit __c11_atomic_fetch_sub
161
162#define atomic_fetch_or(object, operand) __c11_atomic_fetch_or(object, operand, __ATOMIC_SEQ_CST)
163#define atomic_fetch_or_explicit __c11_atomic_fetch_or
164
165#define atomic_fetch_xor(object, operand) __c11_atomic_fetch_xor(object, operand, __ATOMIC_SEQ_CST)
166#define atomic_fetch_xor_explicit __c11_atomic_fetch_xor
167
168#define atomic_fetch_and(object, operand) __c11_atomic_fetch_and(object, operand, __ATOMIC_SEQ_CST)
169#define atomic_fetch_and_explicit __c11_atomic_fetch_and
170
171/* 7.17.8 Atomic flag type and operations */
172
173typedef struct atomic_flag { atomic_bool _Value; } atomic_flag;
174
175#ifdef __cplusplus
176#define ATOMIC_FLAG_INIT {false}
177#else
178#define ATOMIC_FLAG_INIT { 0 }
179#endif
180
181/* These should be provided by the libc implementation. */
182#ifdef __cplusplus
183bool atomic_flag_test_and_set(volatile atomic_flag *);
184bool atomic_flag_test_and_set_explicit(volatile atomic_flag *, memory_order);
185#else
186_Bool atomic_flag_test_and_set(volatile atomic_flag *);
187_Bool atomic_flag_test_and_set_explicit(volatile atomic_flag *, memory_order);
188#endif
189void atomic_flag_clear(volatile atomic_flag *);
190void atomic_flag_clear_explicit(volatile atomic_flag *, memory_order);
191
192#define atomic_flag_test_and_set(object) __c11_atomic_exchange(&(object)->_Value, 1, __ATOMIC_SEQ_CST)
193#define atomic_flag_test_and_set_explicit(object, order) __c11_atomic_exchange(&(object)->_Value, 1, order)
194
195#define atomic_flag_clear(object) __c11_atomic_store(&(object)->_Value, 0, __ATOMIC_SEQ_CST)
196#define atomic_flag_clear_explicit(object, order) __c11_atomic_store(&(object)->_Value, 0, order)
197
198#ifdef __cplusplus
199}
200#endif
201
202#endif /* __STDC_HOSTED__ */
203#endif /* __CLANG_STDATOMIC_H */
204