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Faster atomic loads and stores on windows

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This commit is contained in:
Sergey Vojtovich 2017-12-07 18:36:01 +04:00
parent b04f2a0f01
commit c60095a818
1 changed files with 37 additions and 6 deletions
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43
include/atomic/generic-msvc.h
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@ -61,19 +61,43 @@ static inline int64 my_atomic_add64(int64 volatile *a, int64 v)
return (int64)InterlockedExchangeAdd64((volatile LONGLONG*)a, (LONGLONG)v); return (int64)InterlockedExchangeAdd64((volatile LONGLONG*)a, (LONGLONG)v);
} }
/*
According to MSDN:
Simple reads and writes to properly-aligned 32-bit variables are atomic
operations.
...
Simple reads and writes to properly aligned 64-bit variables are atomic on
64-bit Windows. Reads and writes to 64-bit values are not guaranteed to be
atomic on 32-bit Windows.
https://msdn.microsoft.com/en-us/library/windows/desktop/ms684122(v=vs.85).aspx
*/
static inline int32 my_atomic_load32(int32 volatile *a) static inline int32 my_atomic_load32(int32 volatile *a)
{ {
return (int32)InterlockedCompareExchange((volatile LONG *)a, 0, 0); int32 value= *a;
MemoryBarrier();
return value;
} }
static inline int64 my_atomic_load64(int64 volatile *a) static inline int64 my_atomic_load64(int64 volatile *a)
{ {
return (int64)InterlockedCompareExchange64((volatile LONGLONG *)a, 0, 0); #ifdef _M_X64
int64 value= *a;
MemoryBarrier();
return value;
#else
return (int64) InterlockedCompareExchange64((volatile LONGLONG *) a, 0, 0);
#endif
} }
static inline void* my_atomic_loadptr(void * volatile *a) static inline void* my_atomic_loadptr(void * volatile *a)
{ {
return InterlockedCompareExchangePointer(a, 0, 0); void *value= *a;
MemoryBarrier();
return value;
} }
static inline int32 my_atomic_fas32(int32 volatile *a, int32 v) static inline int32 my_atomic_fas32(int32 volatile *a, int32 v)
@ -93,17 +117,24 @@ static inline void * my_atomic_fasptr(void * volatile *a, void * v)
static inline void my_atomic_store32(int32 volatile *a, int32 v) static inline void my_atomic_store32(int32 volatile *a, int32 v)
{ {
(void)InterlockedExchange((volatile LONG*)a, v); MemoryBarrier();
*a= v;
} }
static inline void my_atomic_store64(int64 volatile *a, int64 v) static inline void my_atomic_store64(int64 volatile *a, int64 v)
{ {
(void)InterlockedExchange64((volatile LONGLONG*)a, v); #ifdef _M_X64
MemoryBarrier();
*a= v;
#else
(void) InterlockedExchange64((volatile LONGLONG *) a, v);
#endif
} }
static inline void my_atomic_storeptr(void * volatile *a, void *v) static inline void my_atomic_storeptr(void * volatile *a, void *v)
{ {
(void)InterlockedExchangePointer(a, v); MemoryBarrier();
*a= v;
} }