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Edit File: zend_atomic.h
/* +----------------------------------------------------------------------+ | This source file is subject to version 3.01 of the PHP license, | | that is bundled with this package in the file LICENSE, and is | | available through the world-wide-web at the following url: | | https://www.php.net/license/3_01.txt | | If you did not receive a copy of the PHP license and are unable to | | obtain it through the world-wide-web, please send a note to | | license@php.net so we can mail you a copy immediately. | +----------------------------------------------------------------------+ | Authors: Levi Morrison <morrison.levi@gmail.com> | +----------------------------------------------------------------------+ */ #ifndef ZEND_ATOMIC_H #define ZEND_ATOMIC_H #include "zend_portability.h" #include <stdbool.h> #define ZEND_GCC_PREREQ(x, y) \ ((__GNUC__ == (x) && __GNUC_MINOR__ >= (y)) || (__GNUC__ > (x))) /* Builtins are used to avoid library linkage */ #if __has_feature(c_atomic) && defined(__clang__) #define HAVE_C11_ATOMICS 1 #elif ZEND_GCC_PREREQ(4, 7) #define HAVE_GNUC_ATOMICS 1 #elif defined(__GNUC__) #define HAVE_SYNC_ATOMICS 1 #elif !defined(ZEND_WIN32) #define HAVE_NO_ATOMICS 1 #endif #undef ZEND_GCC_PREREQ /* Treat zend_atomic_* types as opaque. They have definitions only for size * and alignment purposes. */ #if defined(ZEND_WIN32) || defined(HAVE_SYNC_ATOMICS) typedef struct zend_atomic_bool_s { volatile char value; } zend_atomic_bool; #elif defined(HAVE_C11_ATOMICS) typedef struct zend_atomic_bool_s { _Atomic(bool) value; } zend_atomic_bool; #else typedef struct zend_atomic_bool_s { volatile bool value; } zend_atomic_bool; #endif BEGIN_EXTERN_C() #ifdef ZEND_WIN32 #ifndef InterlockedExchange8 #define InterlockedExchange8 _InterlockedExchange8 #endif #ifndef InterlockedOr8 #define InterlockedOr8 _InterlockedOr8 #endif #define ZEND_ATOMIC_BOOL_INIT(obj, desired) ((obj)->value = (desired)) static zend_always_inline bool zend_atomic_bool_exchange_ex(zend_atomic_bool *obj, bool desired) { return InterlockedExchange8(&obj->value, desired); } /* On this platform it is non-const due to Iterlocked API*/ static zend_always_inline bool zend_atomic_bool_load_ex(zend_atomic_bool *obj) { /* Or'ing with false won't change the value. */ return InterlockedOr8(&obj->value, false); } static zend_always_inline void zend_atomic_bool_store_ex(zend_atomic_bool *obj, bool desired) { (void)InterlockedExchange8(&obj->value, desired); } #elif defined(HAVE_C11_ATOMICS) #define ZEND_ATOMIC_BOOL_INIT(obj, desired) __c11_atomic_init(&(obj)->value, (desired)) static zend_always_inline bool zend_atomic_bool_exchange_ex(zend_atomic_bool *obj, bool desired) { return __c11_atomic_exchange(&obj->value, desired, __ATOMIC_SEQ_CST); } static zend_always_inline bool zend_atomic_bool_load_ex(const zend_atomic_bool *obj) { return __c11_atomic_load(&obj->value, __ATOMIC_SEQ_CST); } static zend_always_inline void zend_atomic_bool_store_ex(zend_atomic_bool *obj, bool desired) { __c11_atomic_store(&obj->value, desired, __ATOMIC_SEQ_CST); } #elif defined(HAVE_GNUC_ATOMICS) #define ZEND_ATOMIC_BOOL_INIT(obj, desired) ((obj)->value = (desired)) static zend_always_inline bool zend_atomic_bool_exchange_ex(zend_atomic_bool *obj, bool desired) { bool prev = false; __atomic_exchange(&obj->value, &desired, &prev, __ATOMIC_SEQ_CST); return prev; } static zend_always_inline bool zend_atomic_bool_load_ex(const zend_atomic_bool *obj) { bool prev = false; __atomic_load(&obj->value, &prev, __ATOMIC_SEQ_CST); return prev; } static zend_always_inline void zend_atomic_bool_store_ex(zend_atomic_bool *obj, bool desired) { __atomic_store(&obj->value, &desired, __ATOMIC_SEQ_CST); } #elif defined(HAVE_SYNC_ATOMICS) #define ZEND_ATOMIC_BOOL_INIT(obj, desired) ((obj)->value = (desired)) static zend_always_inline bool zend_atomic_bool_exchange_ex(zend_atomic_bool *obj, bool desired) { bool prev = __sync_lock_test_and_set(&obj->value, desired); /* __sync_lock_test_and_set only does an acquire barrier, so sync * immediately after. */ __sync_synchronize(); return prev; } static zend_always_inline bool zend_atomic_bool_load_ex(zend_atomic_bool *obj) { /* Or'ing false won't change the value */ return __sync_fetch_and_or(&obj->value, false); } static zend_always_inline void zend_atomic_bool_store_ex(zend_atomic_bool *obj, bool desired) { __sync_synchronize(); obj->value = desired; __sync_synchronize(); } #elif defined(HAVE_NO_ATOMICS) #warning No atomics support detected. Please open an issue with platform details. #define ZEND_ATOMIC_BOOL_INIT(obj, desired) ((obj)->value = (desired)) static zend_always_inline void zend_atomic_bool_store_ex(zend_atomic_bool *obj, bool desired) { obj->value = desired; } static zend_always_inline bool zend_atomic_bool_load_ex(const zend_atomic_bool *obj) { return obj->value; } static zend_always_inline bool zend_atomic_bool_exchange_ex(zend_atomic_bool *obj, bool desired) { bool prev = obj->value; obj->value = desired; return prev; } #endif ZEND_API void zend_atomic_bool_init(zend_atomic_bool *obj, bool desired); ZEND_API bool zend_atomic_bool_exchange(zend_atomic_bool *obj, bool desired); ZEND_API void zend_atomic_bool_store(zend_atomic_bool *obj, bool desired); #if defined(ZEND_WIN32) || defined(HAVE_SYNC_ATOMICS) /* On these platforms it is non-const due to underlying APIs. */ ZEND_API bool zend_atomic_bool_load(zend_atomic_bool *obj); #else ZEND_API bool zend_atomic_bool_load(const zend_atomic_bool *obj); #endif END_EXTERN_C() #endif