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#ifndef AL_ATOMIC_H
#define AL_ATOMIC_H
#include "static_assert.h"
#include "bool.h"
#ifdef __cplusplus
extern "C" {
#endif
/* Atomics using C11 */
#ifdef HAVE_C11_ATOMIC
#include <stdatomic.h>
#define almemory_order memory_order
#define almemory_order_relaxed memory_order_relaxed
#define almemory_order_consume memory_order_consume
#define almemory_order_acquire memory_order_acquire
#define almemory_order_release memory_order_release
#define almemory_order_acq_rel memory_order_acq_rel
#define almemory_order_seq_cst memory_order_seq_cst
#define ATOMIC(T) T _Atomic
#define ATOMIC_INIT(_val, _newval) atomic_init((_val), (_newval))
#define ATOMIC_INIT_STATIC(_newval) ATOMIC_VAR_INIT(_newval)
#define PARAM2(f, a, b, ...) (f((a), (b)))
#define PARAM3(f, a, b, c, ...) (f((a), (b), (c)))
#define PARAM5(f, a, b, c, d, e, ...) (f((a), (b), (c), (d), (e)))
#define ATOMIC_LOAD(...) PARAM2(atomic_load_explicit, __VA_ARGS__, memory_order_seq_cst)
#define ATOMIC_STORE(...) PARAM3(atomic_store_explicit, __VA_ARGS__, memory_order_seq_cst)
#define ATOMIC_ADD(...) PARAM3(atomic_fetch_add_explicit, __VA_ARGS__, memory_order_seq_cst)
#define ATOMIC_SUB(...) PARAM3(atomic_fetch_sub_explicit, __VA_ARGS__, memory_order_seq_cst)
#define ATOMIC_EXCHANGE(T, ...) PARAM3(atomic_exchange_explicit, __VA_ARGS__, memory_order_seq_cst)
#define ATOMIC_COMPARE_EXCHANGE_STRONG(T, ...) \
PARAM5(atomic_compare_exchange_strong_explicit, __VA_ARGS__, memory_order_seq_cst, memory_order_seq_cst)
#define ATOMIC_COMPARE_EXCHANGE_WEAK(T, ...) \
PARAM5(atomic_compare_exchange_weak_explicit, __VA_ARGS__, memory_order_seq_cst, memory_order_seq_cst)
#define ATOMIC_THREAD_FENCE atomic_thread_fence
/* Atomics using GCC intrinsics */
#elif defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)) && !defined(__QNXNTO__)
enum almemory_order {
almemory_order_relaxed,
almemory_order_consume,
almemory_order_acquire,
almemory_order_release,
almemory_order_acq_rel,
almemory_order_seq_cst
};
#define ATOMIC(T) struct { T volatile value; }
#define ATOMIC_INIT(_val, _newval) do { (_val)->value = (_newval); } while(0)
#define ATOMIC_INIT_STATIC(_newval) {(_newval)}
#define ATOMIC_LOAD(_val, ...) __extension__({ \
__typeof((_val)->value) _r = (_val)->value; \
__asm__ __volatile__("" ::: "memory"); \
_r; \
})
#define ATOMIC_STORE(_val, _newval, ...) do { \
__asm__ __volatile__("" ::: "memory"); \
(_val)->value = (_newval); \
} while(0)
#define ATOMIC_ADD(_val, _incr, ...) __sync_fetch_and_add(&(_val)->value, (_incr))
#define ATOMIC_SUB(_val, _decr, ...) __sync_fetch_and_sub(&(_val)->value, (_decr))
#define ATOMIC_EXCHANGE(T, _val, _newval, ...) __extension__({ \
static_assert(sizeof(T)==sizeof((_val)->value), "Type "#T" has incorrect size!"); \
__sync_lock_test_and_set(&(_val)->value, (_newval)); \
})
#define ATOMIC_COMPARE_EXCHANGE_STRONG(T, _val, _oldval, _newval, ...) __extension__({ \
static_assert(sizeof(T)==sizeof((_val)->value), "Type "#T" has incorrect size!"); \
T _o = *(_oldval); \
*(_oldval) = __sync_val_compare_and_swap(&(_val)->value, _o, (_newval)); \
*(_oldval) == _o; \
})
#define ATOMIC_THREAD_FENCE(order) do { \
enum { must_be_constant = (order) }; \
const int _o = must_be_constant; \
if(_o > almemory_order_relaxed) \
__asm__ __volatile__("" ::: "memory"); \
} while(0)
/* Atomics using x86/x86-64 GCC inline assembly */
#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
#define WRAP_ADD(S, ret, dest, incr) __asm__ __volatile__( \
"lock; xadd"S" %0,(%1)" \
: "=r" (ret) \
: "r" (dest), "0" (incr) \
: "memory" \
)
#define WRAP_SUB(S, ret, dest, decr) __asm__ __volatile__( \
"lock; xadd"S" %0,(%1)" \
: "=r" (ret) \
: "r" (dest), "0" (-(decr)) \
: "memory" \
)
#define WRAP_XCHG(S, ret, dest, newval) __asm__ __volatile__( \
"lock; xchg"S" %0,(%1)" \
: "=r" (ret) \
: "r" (dest), "0" (newval) \
: "memory" \
)
#define WRAP_CMPXCHG(S, ret, dest, oldval, newval) __asm__ __volatile__( \
"lock; cmpxchg"S" %2,(%1)" \
: "=a" (ret) \
: "r" (dest), "r" (newval), "0" (oldval) \
: "memory" \
)
enum almemory_order {
almemory_order_relaxed,
almemory_order_consume,
almemory_order_acquire,
almemory_order_release,
almemory_order_acq_rel,
almemory_order_seq_cst
};
#define ATOMIC(T) struct { T volatile value; }
#define ATOMIC_INIT(_val, _newval) do { (_val)->value = (_newval); } while(0)
#define ATOMIC_INIT_STATIC(_newval) {(_newval)}
#define ATOMIC_LOAD(_val, ...) __extension__({ \
__typeof((_val)->value) _r = (_val)->value; \
__asm__ __volatile__("" ::: "memory"); \
_r; \
})
#define ATOMIC_STORE(_val, _newval, ...) do { \
__asm__ __volatile__("" ::: "memory"); \
(_val)->value = (_newval); \
} while(0)
#define ATOMIC_ADD(_val, _incr, ...) __extension__({ \
static_assert(sizeof((_val)->value)==4 || sizeof((_val)->value)==8, "Unsupported size!"); \
__typeof((_val)->value) _r; \
if(sizeof((_val)->value) == 4) WRAP_ADD("l", _r, &(_val)->value, _incr); \
else if(sizeof((_val)->value) == 8) WRAP_ADD("q", _r, &(_val)->value, _incr); \
_r; \
})
#define ATOMIC_SUB(_val, _decr, ...) __extension__({ \
static_assert(sizeof((_val)->value)==4 || sizeof((_val)->value)==8, "Unsupported size!"); \
__typeof((_val)->value) _r; \
if(sizeof((_val)->value) == 4) WRAP_SUB("l", _r, &(_val)->value, _decr); \
else if(sizeof((_val)->value) == 8) WRAP_SUB("q", _r, &(_val)->value, _decr); \
_r; \
})
#define ATOMIC_EXCHANGE(T, _val, _newval, ...) __extension__({ \
static_assert(sizeof(T)==4 || sizeof(T)==8, "Type "#T" has incorrect size!"); \
static_assert(sizeof(T)==sizeof((_val)->value), "Type "#T" has incorrect size!"); \
T _r; \
if(sizeof(T) == 4) WRAP_XCHG("l", _r, &(_val)->value, (T)(_newval)); \
else if(sizeof(T) == 8) WRAP_XCHG("q", _r, &(_val)->value, (T)(_newval)); \
_r; \
})
#define ATOMIC_COMPARE_EXCHANGE_STRONG(T, _val, _oldval, _newval, ...) __extension__({ \
static_assert(sizeof(T)==4 || sizeof(T)==8, "Type "#T" has incorrect size!"); \
static_assert(sizeof(T)==sizeof((_val)->value), "Type "#T" has incorrect size!"); \
T _old = *(_oldval); \
if(sizeof(T) == 4) WRAP_CMPXCHG("l", *(_oldval), &(_val)->value, _old, (T)(_newval)); \
else if(sizeof(T) == 8) WRAP_CMPXCHG("q", *(_oldval), &(_val)->value, _old, (T)(_newval)); \
*(_oldval) == _old; \
})
#define ATOMIC_THREAD_FENCE(order) do { \
enum { must_be_constant = (order) }; \
const int _o = must_be_constant; \
if(_o > almemory_order_relaxed) \
__asm__ __volatile__("" ::: "memory"); \
} while(0)
/* Atomics using Windows methods */
#elif defined(_WIN32)
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
/* NOTE: This mess is *extremely* noisy, at least on GCC. It works by wrapping
* Windows' 32-bit and 64-bit atomic methods, which are then casted to use the
* given type based on its size (e.g. int and float use 32-bit atomics). This
* is fine for the swap and compare-and-swap methods, although the add and
* subtract methods only work properly for integer types.
*
* Despite how noisy it is, it's unfortunately the only way that doesn't rely
* on C99 (damn MSVC).
*/
inline LONG AtomicAdd32(volatile LONG *dest, LONG incr)
{
return InterlockedExchangeAdd(dest, incr);
}
inline LONGLONG AtomicAdd64(volatile LONGLONG *dest, LONGLONG incr)
{
return InterlockedExchangeAdd64(dest, incr);
}
inline LONG AtomicSub32(volatile LONG *dest, LONG decr)
{
return InterlockedExchangeAdd(dest, -decr);
}
inline LONGLONG AtomicSub64(volatile LONGLONG *dest, LONGLONG decr)
{
return InterlockedExchangeAdd64(dest, -decr);
}
inline LONG AtomicSwap32(volatile LONG *dest, LONG newval)
{
return InterlockedExchange(dest, newval);
}
inline LONGLONG AtomicSwap64(volatile LONGLONG *dest, LONGLONG newval)
{
return InterlockedExchange64(dest, newval);
}
inline bool CompareAndSwap32(volatile LONG *dest, LONG newval, LONG *oldval)
{
LONG old = *oldval;
*oldval = InterlockedCompareExchange(dest, newval, *oldval);
return old == *oldval;
}
inline bool CompareAndSwap64(volatile LONGLONG *dest, LONGLONG newval, LONGLONG *oldval)
{
LONGLONG old = *oldval;
*oldval = InterlockedCompareExchange64(dest, newval, *oldval);
return old == *oldval;
}
#define WRAP_ADDSUB(T, _func, _ptr, _amnt) _func((T volatile*)(_ptr), (_amnt))
#define WRAP_XCHG(T, _func, _ptr, _newval) ((T(*)(T volatile*,T))_func)((_ptr), (_newval))
#define WRAP_CMPXCHG(T, _func, _ptr, _newval, _oldval) ((bool(*)(T volatile*,T,T*))_func)((_ptr), (_newval), (_oldval))
enum almemory_order {
almemory_order_relaxed,
almemory_order_consume,
almemory_order_acquire,
almemory_order_release,
almemory_order_acq_rel,
almemory_order_seq_cst
};
#define ATOMIC(T) struct { T volatile value; }
#define ATOMIC_INIT(_val, _newval) do { (_val)->value = (_newval); } while(0)
#define ATOMIC_INIT_STATIC(_newval) {(_newval)}
#define ATOMIC_LOAD(_val, ...) ((_val)->value)
#define ATOMIC_STORE(_val, _newval, ...) do { \
(_val)->value = (_newval); \
} while(0)
int _al_invalid_atomic_size(); /* not defined */
#define ATOMIC_ADD(_val, _incr, ...) \
((sizeof((_val)->value)==4) ? WRAP_ADDSUB(LONG, AtomicAdd32, &(_val)->value, (_incr)) : \
(sizeof((_val)->value)==8) ? WRAP_ADDSUB(LONGLONG, AtomicAdd64, &(_val)->value, (_incr)) : \
_al_invalid_atomic_size())
#define ATOMIC_SUB(_val, _decr, ...) \
((sizeof((_val)->value)==4) ? WRAP_ADDSUB(LONG, AtomicSub32, &(_val)->value, (_decr)) : \
(sizeof((_val)->value)==8) ? WRAP_ADDSUB(LONGLONG, AtomicSub64, &(_val)->value, (_decr)) : \
_al_invalid_atomic_size())
#define ATOMIC_EXCHANGE(T, _val, _newval, ...) \
((sizeof(T)==4) ? WRAP_XCHG(T, AtomicSwap32, &(_val)->value, (_newval)) : \
(sizeof(T)==8) ? WRAP_XCHG(T, AtomicSwap64, &(_val)->value, (_newval)) : \
(T)_al_invalid_atomic_size())
#define ATOMIC_COMPARE_EXCHANGE_STRONG(T, _val, _oldval, _newval, ...) \
((sizeof(T)==4) ? WRAP_CMPXCHG(T, CompareAndSwap32, &(_val)->value, (_newval), (_oldval)) : \
(sizeof(T)==8) ? WRAP_CMPXCHG(T, CompareAndSwap64, &(_val)->value, (_newval), (_oldval)) : \
(bool)_al_invalid_atomic_size())
#define ATOMIC_THREAD_FENCE(order) do { \
enum { must_be_constant = (order) }; \
const int _o = must_be_constant; \
if(_o > almemory_order_relaxed) \
_ReadWriteBarrier(); \
} while(0)
#else
#error "No atomic functions available on this platform!"
#define ATOMIC(T) T
#define ATOMIC_INIT_STATIC(_newval) (0)
#define ATOMIC_LOAD_UNSAFE(_val) (0)
#define ATOMIC_STORE_UNSAFE(_val, _newval) ((void)0)
#define ATOMIC_LOAD(_val, ...) (0)
#define ATOMIC_STORE(_val, _newval, ...) ((void)0)
#define ATOMIC_ADD(_val, _incr, ...) (0)
#define ATOMIC_SUB(_val, _decr, ...) (0)
#define ATOMIC_EXCHANGE(T, _val, _newval, ...) (0)
#define ATOMIC_COMPARE_EXCHANGE_STRONG(T, _val, _oldval, _newval, ...) (0)
#endif
/* If no weak cmpxchg is provided (not all systems will have one), substitute a
* strong cmpxchg. */
#ifndef ATOMIC_COMPARE_EXCHANGE_WEAK
#define ATOMIC_COMPARE_EXCHANGE_WEAK ATOMIC_COMPARE_EXCHANGE_STRONG
#endif
typedef unsigned int uint;
typedef ATOMIC(uint) RefCount;
inline void InitRef(RefCount *ptr, uint value)
{ ATOMIC_INIT(ptr, value); }
inline uint ReadRef(RefCount *ptr)
{ return ATOMIC_LOAD(ptr); }
inline uint IncrementRef(RefCount *ptr)
{ return ATOMIC_ADD(ptr, 1)+1; }
inline uint DecrementRef(RefCount *ptr)
{ return ATOMIC_SUB(ptr, 1)-1; }
#ifdef __cplusplus
}
#endif
#endif /* AL_ATOMIC_H */
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