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Diffstat (limited to 'mesalib/src/util/u_atomic.h')
| -rw-r--r-- | mesalib/src/util/u_atomic.h | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/mesalib/src/util/u_atomic.h b/mesalib/src/util/u_atomic.h new file mode 100644 index 000000000..401003638 --- /dev/null +++ b/mesalib/src/util/u_atomic.h @@ -0,0 +1,188 @@ +/** + * Many similar implementations exist. See for example libwsbm + * or the linux kernel include/atomic.h + * + * No copyright claimed on this file. + * + */ + +#ifndef U_ATOMIC_H +#define U_ATOMIC_H + +#include <stdbool.h> + +/* Favor OS-provided implementations. + * + * Where no OS-provided implementation is available, fall back to + * locally coded assembly, compiler intrinsic or ultimately a + * mutex-based implementation. + */ +#if defined(__sun) +#define PIPE_ATOMIC_OS_SOLARIS +#elif defined(_MSC_VER) +#define PIPE_ATOMIC_MSVC_INTRINSIC +#elif defined(__GNUC__) +#define PIPE_ATOMIC_GCC_INTRINSIC +#else +#error "Unsupported platform" +#endif + + +/* Implementation using GCC-provided synchronization intrinsics + */ +#if defined(PIPE_ATOMIC_GCC_INTRINSIC) + +#define PIPE_ATOMIC "GCC Sync Intrinsics" + +#define p_atomic_set(_v, _i) (*(_v) = (_i)) +#define p_atomic_read(_v) (*(_v)) +#define p_atomic_dec_zero(v) (__sync_sub_and_fetch((v), 1) == 0) +#define p_atomic_inc(v) (void) __sync_add_and_fetch((v), 1) +#define p_atomic_dec(v) (void) __sync_sub_and_fetch((v), 1) +#define p_atomic_inc_return(v) __sync_add_and_fetch((v), 1) +#define p_atomic_dec_return(v) __sync_sub_and_fetch((v), 1) +#define p_atomic_cmpxchg(v, old, _new) \ + __sync_val_compare_and_swap((v), (old), (_new)) + +#endif + + + +/* Unlocked version for single threaded environments, such as some + * windows kernel modules. + */ +#if defined(PIPE_ATOMIC_OS_UNLOCKED) + +#define PIPE_ATOMIC "Unlocked" + +#define p_atomic_set(_v, _i) (*(_v) = (_i)) +#define p_atomic_read(_v) (*(_v)) +#define p_atomic_dec_zero(_v) (p_atomic_dec_return(_v) == 0) +#define p_atomic_inc(_v) ((void) p_atomic_inc_return(_v)) +#define p_atomic_dec(_v) ((void) p_atomic_dec_return(_v)) +#define p_atomic_inc_return(_v) (++(*(_v))) +#define p_atomic_dec_return(_v) (--(*(_v))) +#define p_atomic_cmpxchg(_v, _old, _new) (*(_v) == (_old) ? (*(_v) = (_new), (_old)) : *(_v)) + +#endif + + +#if defined(PIPE_ATOMIC_MSVC_INTRINSIC) + +#define PIPE_ATOMIC "MSVC Intrinsics" + +/* We use the Windows header's Interlocked* functions instead of the + * _Interlocked* intrinsics wherever we can, as support for the latter varies + * with target CPU, whereas Windows headers take care of all portability + * issues: using intrinsics where available, falling back to library + * implementations where not. + */ +#ifndef WIN32_LEAN_AND_MEAN +#define WIN32_LEAN_AND_MEAN 1 +#endif +#include <windows.h> +#include <intrin.h> +#include <assert.h> + +#pragma intrinsic(_InterlockedCompareExchange8) + +/* MSVC supports decltype keyword, but it's only supported on C++ and doesn't + * quite work here; and if a C++-only solution is worthwhile, then it would be + * better to use templates / function overloading, instead of decltype magic. + * Therefore, we rely on implicit casting to LONGLONG for the functions that return + */ + +#define p_atomic_set(_v, _i) (*(_v) = (_i)) +#define p_atomic_read(_v) (*(_v)) + +#define p_atomic_dec_zero(_v) \ + (p_atomic_dec_return(_v) == 0) + +#define p_atomic_inc(_v) \ + ((void) p_atomic_inc_return(_v)) + +#define p_atomic_inc_return(_v) (\ + sizeof *(_v) == sizeof(short) ? InterlockedIncrement16((short *) (_v)) : \ + sizeof *(_v) == sizeof(long) ? InterlockedIncrement ((long *) (_v)) : \ + sizeof *(_v) == sizeof(__int64) ? InterlockedIncrement64((__int64 *)(_v)) : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_dec(_v) \ + ((void) p_atomic_dec_return(_v)) + +#define p_atomic_dec_return(_v) (\ + sizeof *(_v) == sizeof(short) ? InterlockedDecrement16((short *) (_v)) : \ + sizeof *(_v) == sizeof(long) ? InterlockedDecrement ((long *) (_v)) : \ + sizeof *(_v) == sizeof(__int64) ? InterlockedDecrement64((__int64 *)(_v)) : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_cmpxchg(_v, _old, _new) (\ + sizeof *(_v) == sizeof(char) ? _InterlockedCompareExchange8((char *) (_v), (char) (_new), (char) (_old)) : \ + sizeof *(_v) == sizeof(short) ? InterlockedCompareExchange16((short *) (_v), (short) (_new), (short) (_old)) : \ + sizeof *(_v) == sizeof(long) ? InterlockedCompareExchange ((long *) (_v), (long) (_new), (long) (_old)) : \ + sizeof *(_v) == sizeof(__int64) ? InterlockedCompareExchange64((__int64 *)(_v), (__int64)(_new), (__int64)(_old)) : \ + (assert(!"should not get here"), 0)) + +#endif + +#if defined(PIPE_ATOMIC_OS_SOLARIS) + +#define PIPE_ATOMIC "Solaris OS atomic functions" + +#include <atomic.h> +#include <assert.h> + +#define p_atomic_set(_v, _i) (*(_v) = (_i)) +#define p_atomic_read(_v) (*(_v)) + +#define p_atomic_dec_zero(v) (\ + sizeof(*v) == sizeof(uint8_t) ? atomic_dec_8_nv ((uint8_t *)(v)) == 0 : \ + sizeof(*v) == sizeof(uint16_t) ? atomic_dec_16_nv((uint16_t *)(v)) == 0 : \ + sizeof(*v) == sizeof(uint32_t) ? atomic_dec_32_nv((uint32_t *)(v)) == 0 : \ + sizeof(*v) == sizeof(uint64_t) ? atomic_dec_64_nv((uint64_t *)(v)) == 0 : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_inc(v) (void) (\ + sizeof(*v) == sizeof(uint8_t) ? atomic_inc_8 ((uint8_t *)(v)) : \ + sizeof(*v) == sizeof(uint16_t) ? atomic_inc_16((uint16_t *)(v)) : \ + sizeof(*v) == sizeof(uint32_t) ? atomic_inc_32((uint32_t *)(v)) : \ + sizeof(*v) == sizeof(uint64_t) ? atomic_inc_64((uint64_t *)(v)) : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_inc_return(v) ((typeof(*v)) \ + sizeof(*v) == sizeof(uint8_t) ? atomic_inc_8_nv ((uint8_t *)(v)) : \ + sizeof(*v) == sizeof(uint16_t) ? atomic_inc_16_nv((uint16_t *)(v)) : \ + sizeof(*v) == sizeof(uint32_t) ? atomic_inc_32_nv((uint32_t *)(v)) : \ + sizeof(*v) == sizeof(uint64_t) ? atomic_inc_64_nv((uint64_t *)(v)) : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_dec(v) ((void) \ + sizeof(*v) == sizeof(uint8_t) ? atomic_dec_8 ((uint8_t *)(v)) : \ + sizeof(*v) == sizeof(uint16_t) ? atomic_dec_16((uint16_t *)(v)) : \ + sizeof(*v) == sizeof(uint32_t) ? atomic_dec_32((uint32_t *)(v)) : \ + sizeof(*v) == sizeof(uint64_t) ? atomic_dec_64((uint64_t *)(v)) : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_dec_return(v) ((typeof(*v)) \ + sizeof(*v) == sizeof(uint8_t) ? atomic_dec_8_nv ((uint8_t *)(v)) : \ + sizeof(*v) == sizeof(uint16_t) ? atomic_dec_16_nv((uint16_t *)(v)) : \ + sizeof(*v) == sizeof(uint32_t) ? atomic_dec_32_nv((uint32_t *)(v)) : \ + sizeof(*v) == sizeof(uint64_t) ? atomic_dec_64_nv((uint64_t *)(v)) : \ + (assert(!"should not get here"), 0)) + +#define p_atomic_cmpxchg(v, old, _new) ((typeof(*v)) \ + sizeof(*v) == sizeof(uint8_t) ? atomic_cas_8 ((uint8_t *)(v), (uint8_t )(old), (uint8_t )(_new)) : \ + sizeof(*v) == sizeof(uint16_t) ? atomic_cas_16((uint16_t *)(v), (uint16_t)(old), (uint16_t)(_new)) : \ + sizeof(*v) == sizeof(uint32_t) ? atomic_cas_32((uint32_t *)(v), (uint32_t)(old), (uint32_t)(_new)) : \ + sizeof(*v) == sizeof(uint64_t) ? atomic_cas_64((uint64_t *)(v), (uint64_t)(old), (uint64_t)(_new)) : \ + (assert(!"should not get here"), 0)) + +#endif + +#ifndef PIPE_ATOMIC +#error "No pipe_atomic implementation selected" +#endif + + + +#endif /* U_ATOMIC_H */ |