libstdc++
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00001 // -*- C++ -*- header. 00002 00003 // Copyright (C) 2008, 2009 00004 // Free Software Foundation, Inc. 00005 // 00006 // This file is part of the GNU ISO C++ Library. This library is free 00007 // software; you can redistribute it and/or modify it under the 00008 // terms of the GNU General Public License as published by the 00009 // Free Software Foundation; either version 3, or (at your option) 00010 // any later version. 00011 00012 // This library is distributed in the hope that it will be useful, 00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00015 // GNU General Public License for more details. 00016 00017 // Under Section 7 of GPL version 3, you are granted additional 00018 // permissions described in the GCC Runtime Library Exception, version 00019 // 3.1, as published by the Free Software Foundation. 00020 00021 // You should have received a copy of the GNU General Public License and 00022 // a copy of the GCC Runtime Library Exception along with this program; 00023 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 00024 // <http://www.gnu.org/licenses/>. 00025 00026 /** @file bits/atomic_0.h 00027 * This is an internal header file, included by other library headers. 00028 * You should not attempt to use it directly. 00029 */ 00030 00031 #ifndef _GLIBCXX_ATOMIC_0_H 00032 #define _GLIBCXX_ATOMIC_0_H 1 00033 00034 #pragma GCC system_header 00035 00036 // _GLIBCXX_BEGIN_NAMESPACE(std) 00037 00038 // 0 == __atomic0 == Never lock-free 00039 namespace __atomic0 00040 { 00041 struct atomic_flag; 00042 00043 // Implementation specific defines. 00044 #define _ATOMIC_LOAD_(__a, __x) \ 00045 ({ volatile __typeof__ _ATOMIC_MEMBER_* __p = &_ATOMIC_MEMBER_; \ 00046 volatile __atomic_flag_base* __g = __atomic_flag_for_address(__p); \ 00047 __atomic_flag_wait_explicit(__g, __x); \ 00048 __typeof__ _ATOMIC_MEMBER_ __r = *__p; \ 00049 atomic_flag_clear_explicit(__g, __x); \ 00050 __r; }) 00051 00052 #define _ATOMIC_STORE_(__a, __m, __x) \ 00053 ({ volatile __typeof__ _ATOMIC_MEMBER_* __p = &_ATOMIC_MEMBER_; \ 00054 __typeof__(__m) __v = (__m); \ 00055 volatile __atomic_flag_base* __g = __atomic_flag_for_address(__p); \ 00056 __atomic_flag_wait_explicit(__g, __x); \ 00057 *__p = __v; \ 00058 atomic_flag_clear_explicit(__g, __x); \ 00059 __v; }) 00060 00061 #define _ATOMIC_MODIFY_(__a, __o, __m, __x) \ 00062 ({ volatile __typeof__ _ATOMIC_MEMBER_* __p = &_ATOMIC_MEMBER_; \ 00063 __typeof__(__m) __v = (__m); \ 00064 volatile __atomic_flag_base* __g = __atomic_flag_for_address(__p); \ 00065 __atomic_flag_wait_explicit(__g, __x); \ 00066 __typeof__ _ATOMIC_MEMBER_ __r = *__p; \ 00067 *__p __o __v; \ 00068 atomic_flag_clear_explicit(__g, __x); \ 00069 __r; }) 00070 00071 #define _ATOMIC_CMPEXCHNG_(__a, __e, __m, __x) \ 00072 ({ volatile __typeof__ _ATOMIC_MEMBER_* __p = &_ATOMIC_MEMBER_; \ 00073 __typeof__(__e) __q = (__e); \ 00074 __typeof__(__m) __v = (__m); \ 00075 bool __r; \ 00076 volatile __atomic_flag_base* __g = __atomic_flag_for_address(__p); \ 00077 __atomic_flag_wait_explicit(__g, __x); \ 00078 __typeof__ _ATOMIC_MEMBER_ __t__ = *__p; \ 00079 if (__t__ == *__q) { *__p = __v; __r = true; } \ 00080 else { *__q = __t__; __r = false; } \ 00081 atomic_flag_clear_explicit(__g, __x); \ 00082 __r; }) 00083 00084 /// atomic_flag 00085 struct atomic_flag : public __atomic_flag_base 00086 { 00087 atomic_flag() = default; 00088 ~atomic_flag() = default; 00089 atomic_flag(const atomic_flag&) = delete; 00090 atomic_flag& operator=(const atomic_flag&) = delete; 00091 00092 // Conversion to ATOMIC_FLAG_INIT. 00093 atomic_flag(bool __i): __atomic_flag_base({ __i }) { } 00094 00095 bool 00096 test_and_set(memory_order __m = memory_order_seq_cst) volatile; 00097 00098 void 00099 clear(memory_order __m = memory_order_seq_cst) volatile; 00100 }; 00101 00102 /// 29.4.2, address types 00103 struct atomic_address 00104 { 00105 private: 00106 void* _M_i; 00107 00108 public: 00109 atomic_address() = default; 00110 ~atomic_address() = default; 00111 atomic_address(const atomic_address&) = delete; 00112 atomic_address& operator=(const atomic_address&) = delete; 00113 00114 atomic_address(void* __v) { _M_i = __v; } 00115 00116 bool 00117 is_lock_free() const volatile 00118 { return false; } 00119 00120 void 00121 store(void* __v, memory_order __m = memory_order_seq_cst) volatile 00122 { 00123 __glibcxx_assert(__m != memory_order_acquire); 00124 __glibcxx_assert(__m != memory_order_acq_rel); 00125 __glibcxx_assert(__m != memory_order_consume); 00126 _ATOMIC_STORE_(this, __v, __m); 00127 } 00128 00129 void* 00130 load(memory_order __m = memory_order_seq_cst) const volatile 00131 { 00132 __glibcxx_assert(__m != memory_order_release); 00133 __glibcxx_assert(__m != memory_order_acq_rel); 00134 return _ATOMIC_LOAD_(this, __m); 00135 } 00136 00137 void* 00138 exchange(void* __v, memory_order __m = memory_order_seq_cst) volatile 00139 { return _ATOMIC_MODIFY_(this, =, __v, __m); } 00140 00141 bool 00142 compare_exchange_weak(void*& __v1, void* __v2, memory_order __m1, 00143 memory_order __m2) volatile 00144 { 00145 __glibcxx_assert(__m2 != memory_order_release); 00146 __glibcxx_assert(__m2 != memory_order_acq_rel); 00147 __glibcxx_assert(__m2 <= __m1); 00148 return _ATOMIC_CMPEXCHNG_(this, &__v1, __v2, __m1); 00149 } 00150 00151 bool 00152 compare_exchange_weak(void*& __v1, void* __v2, 00153 memory_order __m = memory_order_seq_cst) volatile 00154 { 00155 return compare_exchange_weak(__v1, __v2, __m, 00156 __calculate_memory_order(__m)); 00157 } 00158 00159 bool 00160 compare_exchange_strong(void*& __v1, void* __v2, memory_order __m1, 00161 memory_order __m2) volatile 00162 { 00163 __glibcxx_assert(__m2 != memory_order_release); 00164 __glibcxx_assert(__m2 != memory_order_acq_rel); 00165 __glibcxx_assert(__m2 <= __m1); 00166 return _ATOMIC_CMPEXCHNG_(this, &__v1, __v2, __m1); 00167 } 00168 00169 bool 00170 compare_exchange_strong(void*& __v1, void* __v2, 00171 memory_order __m = memory_order_seq_cst) volatile 00172 { 00173 return compare_exchange_strong(__v1, __v2, __m, 00174 __calculate_memory_order(__m)); 00175 } 00176 00177 void* 00178 fetch_add(ptrdiff_t __d, memory_order __m = memory_order_seq_cst) volatile 00179 { 00180 void* volatile* __p = &(_M_i); 00181 volatile __atomic_flag_base* __g = __atomic_flag_for_address(__p); 00182 __atomic_flag_wait_explicit(__g, __m); 00183 void* __r = *__p; 00184 *__p = (void*)((char*)(*__p) + __d); 00185 atomic_flag_clear_explicit(__g, __m); 00186 return __r; 00187 } 00188 00189 void* 00190 fetch_sub(ptrdiff_t __d, memory_order __m = memory_order_seq_cst) volatile 00191 { 00192 void* volatile* __p = &(_M_i); 00193 volatile __atomic_flag_base* __g = __atomic_flag_for_address(__p); 00194 __atomic_flag_wait_explicit(__g, __m); 00195 void* __r = *__p; 00196 *__p = (void*)((char*)(*__p) - __d); 00197 atomic_flag_clear_explicit(__g, __m); 00198 return __r; 00199 } 00200 00201 operator void*() const volatile 00202 { return load(); } 00203 00204 void* 00205 operator=(void* __v) // XXX volatile 00206 { 00207 store(__v); 00208 return __v; 00209 } 00210 00211 void* 00212 operator+=(ptrdiff_t __d) volatile 00213 { return fetch_add(__d) + __d; } 00214 00215 void* 00216 operator-=(ptrdiff_t __d) volatile 00217 { return fetch_sub(__d) - __d; } 00218 }; 00219 00220 00221 // 29.3.1 atomic integral types 00222 // For each of the integral types, define atomic_[integral type] struct 00223 // 00224 // atomic_bool bool 00225 // atomic_char char 00226 // atomic_schar signed char 00227 // atomic_uchar unsigned char 00228 // atomic_short short 00229 // atomic_ushort unsigned short 00230 // atomic_int int 00231 // atomic_uint unsigned int 00232 // atomic_long long 00233 // atomic_ulong unsigned long 00234 // atomic_llong long long 00235 // atomic_ullong unsigned long long 00236 // atomic_char16_t char16_t 00237 // atomic_char32_t char32_t 00238 // atomic_wchar_t wchar_t 00239 00240 // Base type. 00241 // NB: Assuming _ITp is an integral scalar type that is 1, 2, 4, or 8 bytes, 00242 // since that is what GCC built-in functions for atomic memory access work on. 00243 template<typename _ITp> 00244 struct __atomic_base 00245 { 00246 private: 00247 typedef _ITp __integral_type; 00248 00249 __integral_type _M_i; 00250 00251 public: 00252 __atomic_base() = default; 00253 ~__atomic_base() = default; 00254 __atomic_base(const __atomic_base&) = delete; 00255 __atomic_base& operator=(const __atomic_base&) = delete; 00256 00257 // Requires __integral_type convertible to _M_base._M_i. 00258 __atomic_base(__integral_type __i) { _M_i = __i; } 00259 00260 operator __integral_type() const volatile 00261 { return load(); } 00262 00263 __integral_type 00264 operator=(__integral_type __i) // XXX volatile 00265 { 00266 store(__i); 00267 return __i; 00268 } 00269 00270 __integral_type 00271 operator++(int) volatile 00272 { return fetch_add(1); } 00273 00274 __integral_type 00275 operator--(int) volatile 00276 { return fetch_sub(1); } 00277 00278 __integral_type 00279 operator++() volatile 00280 { return fetch_add(1) + 1; } 00281 00282 __integral_type 00283 operator--() volatile 00284 { return fetch_sub(1) - 1; } 00285 00286 __integral_type 00287 operator+=(__integral_type __i) volatile 00288 { return fetch_add(__i) + __i; } 00289 00290 __integral_type 00291 operator-=(__integral_type __i) volatile 00292 { return fetch_sub(__i) - __i; } 00293 00294 __integral_type 00295 operator&=(__integral_type __i) volatile 00296 { return fetch_and(__i) & __i; } 00297 00298 __integral_type 00299 operator|=(__integral_type __i) volatile 00300 { return fetch_or(__i) | __i; } 00301 00302 __integral_type 00303 operator^=(__integral_type __i) volatile 00304 { return fetch_xor(__i) ^ __i; } 00305 00306 bool 00307 is_lock_free() const volatile 00308 { return false; } 00309 00310 void 00311 store(__integral_type __i, 00312 memory_order __m = memory_order_seq_cst) volatile 00313 { 00314 __glibcxx_assert(__m != memory_order_acquire); 00315 __glibcxx_assert(__m != memory_order_acq_rel); 00316 __glibcxx_assert(__m != memory_order_consume); 00317 _ATOMIC_STORE_(this, __i, __m); 00318 } 00319 00320 __integral_type 00321 load(memory_order __m = memory_order_seq_cst) const volatile 00322 { 00323 __glibcxx_assert(__m != memory_order_release); 00324 __glibcxx_assert(__m != memory_order_acq_rel); 00325 return _ATOMIC_LOAD_(this, __m); 00326 } 00327 00328 __integral_type 00329 exchange(__integral_type __i, 00330 memory_order __m = memory_order_seq_cst) volatile 00331 { return _ATOMIC_MODIFY_(this, =, __i, __m); } 00332 00333 bool 00334 compare_exchange_weak(__integral_type& __i1, __integral_type __i2, 00335 memory_order __m1, memory_order __m2) volatile 00336 { 00337 __glibcxx_assert(__m2 != memory_order_release); 00338 __glibcxx_assert(__m2 != memory_order_acq_rel); 00339 __glibcxx_assert(__m2 <= __m1); 00340 return _ATOMIC_CMPEXCHNG_(this, &__i1, __i2, __m1); 00341 } 00342 00343 bool 00344 compare_exchange_weak(__integral_type& __i1, __integral_type __i2, 00345 memory_order __m = memory_order_seq_cst) volatile 00346 { 00347 return compare_exchange_weak(__i1, __i2, __m, 00348 __calculate_memory_order(__m)); 00349 } 00350 00351 bool 00352 compare_exchange_strong(__integral_type& __i1, __integral_type __i2, 00353 memory_order __m1, memory_order __m2) volatile 00354 { 00355 __glibcxx_assert(__m2 != memory_order_release); 00356 __glibcxx_assert(__m2 != memory_order_acq_rel); 00357 __glibcxx_assert(__m2 <= __m1); 00358 return _ATOMIC_CMPEXCHNG_(this, &__i1, __i2, __m1); 00359 } 00360 00361 bool 00362 compare_exchange_strong(__integral_type& __i1, __integral_type __i2, 00363 memory_order __m = memory_order_seq_cst) volatile 00364 { 00365 return compare_exchange_strong(__i1, __i2, __m, 00366 __calculate_memory_order(__m)); 00367 } 00368 00369 __integral_type 00370 fetch_add(__integral_type __i, 00371 memory_order __m = memory_order_seq_cst) volatile 00372 { return _ATOMIC_MODIFY_(this, +=, __i, __m); } 00373 00374 __integral_type 00375 fetch_sub(__integral_type __i, 00376 memory_order __m = memory_order_seq_cst) volatile 00377 { return _ATOMIC_MODIFY_(this, -=, __i, __m); } 00378 00379 __integral_type 00380 fetch_and(__integral_type __i, 00381 memory_order __m = memory_order_seq_cst) volatile 00382 { return _ATOMIC_MODIFY_(this, &=, __i, __m); } 00383 00384 __integral_type 00385 fetch_or(__integral_type __i, 00386 memory_order __m = memory_order_seq_cst) volatile 00387 { return _ATOMIC_MODIFY_(this, |=, __i, __m); } 00388 00389 __integral_type 00390 fetch_xor(__integral_type __i, 00391 memory_order __m = memory_order_seq_cst) volatile 00392 { return _ATOMIC_MODIFY_(this, ^=, __i, __m); } 00393 }; 00394 00395 00396 /// atomic_bool 00397 // NB: No operators or fetch-operations for this type. 00398 struct atomic_bool 00399 { 00400 private: 00401 __atomic_base<bool> _M_base; 00402 00403 public: 00404 atomic_bool() = default; 00405 ~atomic_bool() = default; 00406 atomic_bool(const atomic_bool&) = delete; 00407 atomic_bool& operator=(const atomic_bool&) = delete; 00408 00409 atomic_bool(bool __i) : _M_base(__i) { } 00410 00411 bool 00412 operator=(bool __i) // XXX volatile 00413 { return _M_base.operator=(__i); } 00414 00415 operator bool() const volatile 00416 { return _M_base.load(); } 00417 00418 bool 00419 is_lock_free() const volatile 00420 { return _M_base.is_lock_free(); } 00421 00422 void 00423 store(bool __i, memory_order __m = memory_order_seq_cst) volatile 00424 { _M_base.store(__i, __m); } 00425 00426 bool 00427 load(memory_order __m = memory_order_seq_cst) const volatile 00428 { return _M_base.load(__m); } 00429 00430 bool 00431 exchange(bool __i, memory_order __m = memory_order_seq_cst) volatile 00432 { return _M_base.exchange(__i, __m); } 00433 00434 bool 00435 compare_exchange_weak(bool& __i1, bool __i2, memory_order __m1, 00436 memory_order __m2) volatile 00437 { return _M_base.compare_exchange_weak(__i1, __i2, __m1, __m2); } 00438 00439 bool 00440 compare_exchange_weak(bool& __i1, bool __i2, 00441 memory_order __m = memory_order_seq_cst) volatile 00442 { return _M_base.compare_exchange_weak(__i1, __i2, __m); } 00443 00444 bool 00445 compare_exchange_strong(bool& __i1, bool __i2, memory_order __m1, 00446 memory_order __m2) volatile 00447 { return _M_base.compare_exchange_strong(__i1, __i2, __m1, __m2); } 00448 00449 00450 bool 00451 compare_exchange_strong(bool& __i1, bool __i2, 00452 memory_order __m = memory_order_seq_cst) volatile 00453 { return _M_base.compare_exchange_strong(__i1, __i2, __m); } 00454 }; 00455 00456 #undef _ATOMIC_LOAD_ 00457 #undef _ATOMIC_STORE_ 00458 #undef _ATOMIC_MODIFY_ 00459 #undef _ATOMIC_CMPEXCHNG_ 00460 } // namespace __atomic0 00461 00462 // _GLIBCXX_END_NAMESPACE 00463 00464 #endif