/simpletypesystem/trunk : revision 86

1

/*

2

* An implementation of C11 stdatomic.h directly borrowed from FreeBSD

3

* (original copyright follows), with minor modifications for

4

* portability to other systems. Works for recent Clang (that

5

* implement the feature c_atomic) and GCC 4.7+; includes

6

* compatibility for GCC below 4.7 but I wouldn't recommend it.

7

*

8

* Caveats and limitations:

9

* - Only the ``_Atomic parentheses'' notation is implemented, while

10

* the ``_Atomic space'' one is not.

11

* - _Atomic types must be typedef'ed, or programs using them will

12

* not type check correctly (incompatible anonymous structure

13

* types).

14

* - Non-scalar _Atomic types would require runtime support for

15

* runtime locking, which, as far as I know, is not currently

16

* available on any system.

17

*/

18

19

/*-

20

21

* David Chisnall <theraven@FreeBSD.org>

22

23

*

24

* Redistribution and use in source and binary forms, with or without

25

* modification, are permitted provided that the following conditions

26

* are met:

27

* 1. Redistributions of source code must retain the above copyright

28

* notice, this list of conditions and the following disclaimer.

29

* 2. Redistributions in binary form must reproduce the above copyright

30

* notice, this list of conditions and the following disclaimer in the

31

* documentation and/or other materials provided with the distribution.

32

*

33

* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

34

* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

35

* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

36

* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

37

* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

38

* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

39

* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

40

* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

41

* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

42

* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

43

* SUCH DAMAGE.

44

*

45

* $FreeBSD: src/include/stdatomic.h,v 1.10.2.2 2012/05/30 19:21:54 theraven Exp $

46

*/

47

48

#ifndef _STDATOMIC_H_

49

#define _STDATOMIC_H_

50

51

#include <stddef.h>

52

#include <stdint.h>

53

54

#if !defined(__has_feature)

55

#define __has_feature(x) 0

56

#endif

57

#if !defined(__has_builtin)

58

#define __has_builtin(x) 0

59

#endif

60

#if !defined(__GNUC_PREREQ__)

61

#if defined(__GNUC__) && defined(__GNUC_MINOR__)

62

#define __GNUC_PREREQ__(maj, min) \

63

((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))

64

#else

65

#define __GNUC_PREREQ__(maj, min) 0

66

#endif

67

#endif

68

69

#if !defined(__CLANG_ATOMICS) && !defined(__GNUC_ATOMICS)

70

#if __has_feature(c_atomic)

71

#define __CLANG_ATOMICS

72

#elif __GNUC_PREREQ__(4, 7)

73

#define __GNUC_ATOMICS

74

#elif !defined(__GNUC__)

75

#error "stdatomic.h does not support your compiler"

76

#endif

77

#endif

78

79

#if !defined(__CLANG_ATOMICS)

80

#define _Atomic(T) struct { volatile __typeof__(T) __val; }

81

#endif

82

83

/*

84

* 7.17.2 Initialization.

85

*/

86

87

#if defined(__CLANG_ATOMICS)

88

#define ATOMIC_VAR_INIT(value) (value)

89

#define atomic_init(obj, value) __c11_atomic_init(obj, value)

90

#else

91

#define ATOMIC_VAR_INIT(value) { .__val = (value) }

92

#define atomic_init(obj, value) do { \

93

(obj)->__val = (value); \

94

} while (0)

95

#endif

96

97

/*

98

* Clang and recent GCC both provide predefined macros for the memory

99

* orderings. If we are using a compiler that doesn't define them, use the

100

* clang values - these will be ignored in the fallback path.

101

*/

102

103

#ifndef __ATOMIC_RELAXED

104

#define __ATOMIC_RELAXED 0

105

#endif

106

#ifndef __ATOMIC_CONSUME

107

#define __ATOMIC_CONSUME 1

108

#endif

109

#ifndef __ATOMIC_ACQUIRE

110

#define __ATOMIC_ACQUIRE 2

111

#endif

112

#ifndef __ATOMIC_RELEASE

113

#define __ATOMIC_RELEASE 3

114

#endif

115

#ifndef __ATOMIC_ACQ_REL

116

#define __ATOMIC_ACQ_REL 4

117

#endif

118

#ifndef __ATOMIC_SEQ_CST

119

#define __ATOMIC_SEQ_CST 5

120

#endif

121

122

/*

123

* 7.17.3 Order and consistency.

124

*

125

* The memory_order_* constants that denote the barrier behaviour of the

126

* atomic operations.

127

*/

128

129

enum memory_order {

130

memory_order_relaxed = __ATOMIC_RELAXED,

131

memory_order_consume = __ATOMIC_CONSUME,

132

memory_order_acquire = __ATOMIC_ACQUIRE,

133

memory_order_release = __ATOMIC_RELEASE,

134

memory_order_acq_rel = __ATOMIC_ACQ_REL,

135

memory_order_seq_cst = __ATOMIC_SEQ_CST

136

};

137

138

typedef enum memory_order memory_order;

139

140

/*

141

* 7.17.4 Fences.

142

*/

143

144

#ifdef __CLANG_ATOMICS

145

#define atomic_thread_fence(order) __c11_atomic_thread_fence(order)

146

#define atomic_signal_fence(order) __c11_atomic_signal_fence(order)

147

#elif defined(__GNUC_ATOMICS)

148

#define atomic_thread_fence(order) __atomic_thread_fence(order)

149

#define atomic_signal_fence(order) __atomic_signal_fence(order)

150

#else

151

#define atomic_thread_fence(order) __sync_synchronize()

152

#define atomic_signal_fence(order) __asm volatile ("" : : : "memory")

153

#endif

154

155

/*

156

* 7.17.5 Lock-free property.

157

*/

158

159

#if defined(__CLANG_ATOMICS)

160

#define atomic_is_lock_free(obj) \

161

__c11_atomic_is_lock_free(sizeof(obj))

162

#elif defined(__GNUC_ATOMICS)

163

#define atomic_is_lock_free(obj) \

164

__atomic_is_lock_free(sizeof((obj)->__val))

165

#else

166

#define atomic_is_lock_free(obj) \

167

(sizeof((obj)->__val) <= sizeof(void *))

168

#endif

169

170

/*

171

* 7.17.6 Atomic integer types.

172

*/

173

174

typedef _Atomic(_Bool) atomic_bool;

175

typedef _Atomic(char) atomic_char;

176

typedef _Atomic(signed char) atomic_schar;

177

typedef _Atomic(unsigned char) atomic_uchar;

178

typedef _Atomic(short) atomic_short;

179

typedef _Atomic(unsigned short) atomic_ushort;

180

typedef _Atomic(int) atomic_int;

181

typedef _Atomic(unsigned int) atomic_uint;

182

typedef _Atomic(long) atomic_long;

183

typedef _Atomic(unsigned long) atomic_ulong;

184

typedef _Atomic(long long) atomic_llong;

185

typedef _Atomic(unsigned long long) atomic_ullong;

186

#if 0

187

typedef _Atomic(char16_t) atomic_char16_t;

188

typedef _Atomic(char32_t) atomic_char32_t;

189

#endif

190

typedef _Atomic(wchar_t) atomic_wchar_t;

191

typedef _Atomic(int_least8_t) atomic_int_least8_t;

192

typedef _Atomic(uint_least8_t) atomic_uint_least8_t;

193

typedef _Atomic(int_least16_t) atomic_int_least16_t;

194

typedef _Atomic(uint_least16_t) atomic_uint_least16_t;

195

typedef _Atomic(int_least32_t) atomic_int_least32_t;

196

typedef _Atomic(uint_least32_t) atomic_uint_least32_t;

197

typedef _Atomic(int_least64_t) atomic_int_least64_t;

198

typedef _Atomic(uint_least64_t) atomic_uint_least64_t;

199

typedef _Atomic(int_fast8_t) atomic_int_fast8_t;

200

typedef _Atomic(uint_fast8_t) atomic_uint_fast8_t;

201

typedef _Atomic(int_fast16_t) atomic_int_fast16_t;

202

typedef _Atomic(uint_fast16_t) atomic_uint_fast16_t;

203

typedef _Atomic(int_fast32_t) atomic_int_fast32_t;

204

typedef _Atomic(uint_fast32_t) atomic_uint_fast32_t;

205

typedef _Atomic(int_fast64_t) atomic_int_fast64_t;

206

typedef _Atomic(uint_fast64_t) atomic_uint_fast64_t;

207

typedef _Atomic(intptr_t) atomic_intptr_t;

208

typedef _Atomic(uintptr_t) atomic_uintptr_t;

209

typedef _Atomic(size_t) atomic_size_t;

210

typedef _Atomic(ptrdiff_t) atomic_ptrdiff_t;

211

typedef _Atomic(intmax_t) atomic_intmax_t;

212

typedef _Atomic(uintmax_t) atomic_uintmax_t;

213

214

/*

215

* 7.17.7 Operations on atomic types.

216

*/

217

218

/*

219

* Compiler-specific operations.

220

*/

221

222

#if defined(__CLANG_ATOMICS)

223

#define atomic_compare_exchange_strong_explicit(object, expected, \

224

desired, success, failure) \

225

__c11_atomic_compare_exchange_strong(object, expected, desired, \

226

success, failure)

227

#define atomic_compare_exchange_weak_explicit(object, expected, \

228

desired, success, failure) \

229

__c11_atomic_compare_exchange_weak(object, expected, desired, \

230

success, failure)

231

#define atomic_exchange_explicit(object, desired, order) \

232

__c11_atomic_exchange(object, desired, order)

233

#define atomic_fetch_add_explicit(object, operand, order) \

234

__c11_atomic_fetch_add(object, operand, order)

235

#define atomic_fetch_and_explicit(object, operand, order) \

236

__c11_atomic_fetch_and(object, operand, order)

237

#define atomic_fetch_or_explicit(object, operand, order) \

238

__c11_atomic_fetch_or(object, operand, order)

239

#define atomic_fetch_sub_explicit(object, operand, order) \

240

__c11_atomic_fetch_sub(object, operand, order)

241

#define atomic_fetch_xor_explicit(object, operand, order) \

242

__c11_atomic_fetch_xor(object, operand, order)

243

#define atomic_load_explicit(object, order) \

244

__c11_atomic_load(object, order)

245

#define atomic_store_explicit(object, desired, order) \

246

__c11_atomic_store(object, desired, order)

247

#elif defined(__GNUC_ATOMICS)

248

#define atomic_compare_exchange_strong_explicit(object, expected, \

249

desired, success, failure) \

250

__atomic_compare_exchange_n(&(object)->__val, expected, \

251

desired, 0, success, failure)

252

#define atomic_compare_exchange_weak_explicit(object, expected, \

253

desired, success, failure) \

254

__atomic_compare_exchange_n(&(object)->__val, expected, \

255

desired, 1, success, failure)

256

#define atomic_exchange_explicit(object, desired, order) \

257

__atomic_exchange_n(&(object)->__val, desired, order)

258

#define atomic_fetch_add_explicit(object, operand, order) \

259

__atomic_fetch_add(&(object)->__val, operand, order)

260

#define atomic_fetch_and_explicit(object, operand, order) \

261

__atomic_fetch_and(&(object)->__val, operand, order)

262

#define atomic_fetch_or_explicit(object, operand, order) \

263

__atomic_fetch_or(&(object)->__val, operand, order)

264

#define atomic_fetch_sub_explicit(object, operand, order) \

265

__atomic_fetch_sub(&(object)->__val, operand, order)

266

#define atomic_fetch_xor_explicit(object, operand, order) \

267

__atomic_fetch_xor(&(object)->__val, operand, order)

268

#define atomic_load_explicit(object, order) \

269

__atomic_load_n(&(object)->__val, order)

270

#define atomic_store_explicit(object, desired, order) \

271

__atomic_store_n(&(object)->__val, desired, order)

272

#else

273

#define atomic_compare_exchange_strong_explicit(object, expected, \

274

desired, success, failure) ({ \

275

__typeof__((object)->__val) __v; \

276

_Bool __r; \

277

__v = __sync_val_compare_and_swap(&(object)->__val, \

278

*(expected), desired); \

279

__r = *(expected) == __v; \

280

*(expected) = __v; \

281

__r; \

282

})

283

284

#define atomic_compare_exchange_weak_explicit(object, expected, \

285

desired, success, failure) \

286

atomic_compare_exchange_strong_explicit(object, expected, \

287

desired, success, failure)

288

#if __has_builtin(__sync_swap)

289

/* Clang provides a full-barrier atomic exchange - use it if available. */

290

#define atomic_exchange_explicit(object, desired, order) \

291

__sync_swap(&(object)->__val, desired)

292

#else

293

/*

294

* __sync_lock_test_and_set() is only an acquire barrier in theory (although in

295

* practice it is usually a full barrier) so we need an explicit barrier after

296

* it.

297

*/

298

#define atomic_exchange_explicit(object, desired, order) ({ \

299

__typeof__((object)->__val) __v; \

300

__v = __sync_lock_test_and_set(&(object)->__val, desired); \

301

__sync_synchronize(); \

302

__v; \

303

})

304

#endif

305

#define atomic_fetch_add_explicit(object, operand, order) \

306

__sync_fetch_and_add(&(object)->__val, operand)

307

#define atomic_fetch_and_explicit(object, operand, order) \

308

__sync_fetch_and_and(&(object)->__val, operand)

309

#define atomic_fetch_or_explicit(object, operand, order) \

310

__sync_fetch_and_or(&(object)->__val, operand)

311

#define atomic_fetch_sub_explicit(object, operand, order) \

312

__sync_fetch_and_sub(&(object)->__val, operand)

313

#define atomic_fetch_xor_explicit(object, operand, order) \

314

__sync_fetch_and_xor(&(object)->__val, operand)

315

#define atomic_load_explicit(object, order) \

316

__sync_fetch_and_add(&(object)->__val, 0)

317

#define atomic_store_explicit(object, desired, order) do { \

318

__sync_synchronize(); \

319

(object)->__val = (desired); \

320

__sync_synchronize(); \

321

} while (0)

322

#endif

323

324

/*

325

* Convenience functions.

326

*/

327

328

#define atomic_compare_exchange_strong(object, expected, desired) \

329

atomic_compare_exchange_strong_explicit(object, expected, \

330

desired, memory_order_seq_cst, memory_order_seq_cst)

331

#define atomic_compare_exchange_weak(object, expected, desired) \

332

atomic_compare_exchange_weak_explicit(object, expected, \

333

desired, memory_order_seq_cst, memory_order_seq_cst)

334

#define atomic_exchange(object, desired) \

335

atomic_exchange_explicit(object, desired, memory_order_seq_cst)

336

#define atomic_fetch_add(object, operand) \

337

atomic_fetch_add_explicit(object, operand, memory_order_seq_cst)

338

#define atomic_fetch_and(object, operand) \

339

atomic_fetch_and_explicit(object, operand, memory_order_seq_cst)

340

#define atomic_fetch_or(object, operand) \

341

atomic_fetch_or_explicit(object, operand, memory_order_seq_cst)

342

#define atomic_fetch_sub(object, operand) \

343

atomic_fetch_sub_explicit(object, operand, memory_order_seq_cst)

344

#define atomic_fetch_xor(object, operand) \

345

atomic_fetch_xor_explicit(object, operand, memory_order_seq_cst)

346

#define atomic_load(object) \

347

atomic_load_explicit(object, memory_order_seq_cst)

348

#define atomic_store(object, desired) \

349

atomic_store_explicit(object, desired, memory_order_seq_cst)

350

351

/*

352

* 7.17.8 Atomic flag type and operations.

353

*/

354

355

typedef atomic_bool atomic_flag;

356

357

#define ATOMIC_FLAG_INIT ATOMIC_VAR_INIT(0)

358

359

#define atomic_flag_clear_explicit(object, order) \

360

atomic_store_explicit(object, 0, order)

361

#define atomic_flag_test_and_set_explicit(object, order) \

362

atomic_compare_exchange_strong_explicit(object, 0, 1, order, order)

363

364

#define atomic_flag_clear(object) \

365

atomic_flag_clear_explicit(object, memory_order_seq_cst)

366

#define atomic_flag_test_and_set(object) \

367

atomic_flag_test_and_set_explicit(object, memory_order_seq_cst)

368

369

#endif /* !_STDATOMIC_H_ */

370