static void
_dispatch_benchmark_init(void *context)
{
struct __dispatch_benchmark_data_s *bdata = context;
// try and simulate performance of real benchmark as much as possible
// keep 'f', 'c' and 'cnt' in registers
register void (*f)(void *) = bdata->func;
register void *c = bdata->ctxt;
register size_t cnt = bdata->count;
uint64_t start, delta;
#ifdef __LP64__
__uint128_t lcost;
#else
long double lcost;
#endif
kern_return_t kr;
size_t i = 0;
kr = mach_timebase_info(&bdata->tbi);
dispatch_assert_zero(kr);
start = mach_absolute_time();
do {
i++;
f(c);
} while (i < cnt);
delta = mach_absolute_time() - start;
lcost = delta;
lcost *= bdata->tbi.numer;
lcost /= bdata->tbi.denom;
lcost /= cnt;
bdata->loop_cost = lcost;
}
uint64_t
_dispatch_get_nanoseconds(void)
{
struct timeval now;
int r = gettimeofday(&now, NULL);
dispatch_assert_zero(r);
dispatch_assert(sizeof(NSEC_PER_SEC) == 8);
dispatch_assert(sizeof(NSEC_PER_USEC) == 8);
return now.tv_sec * NSEC_PER_SEC + now.tv_usec * NSEC_PER_USEC;
}
uint64_t
_dispatch_get_nanoseconds(void)
{
#if !TARGET_OS_WIN32
struct timeval now;
int r = gettimeofday(&now, NULL);
dispatch_assert_zero(r);
dispatch_assert(sizeof(NSEC_PER_SEC) == 8);
dispatch_assert(sizeof(NSEC_PER_USEC) == 8);
return (uint64_t)now.tv_sec * NSEC_PER_SEC +
(uint64_t)now.tv_usec * NSEC_PER_USEC;
#else /* TARGET_OS_WIN32 */
// FILETIME is 100-nanosecond intervals since January 1, 1601 (UTC).
FILETIME ft;
ULARGE_INTEGER li;
GetSystemTimeAsFileTime(&ft);
li.LowPart = ft.dwLowDateTime;
li.HighPart = ft.dwHighDateTime;
return li.QuadPart * 100ull;
#endif /* TARGET_OS_WIN32 */
}
static void
_dispatch_benchmark_init(void *context)
{
struct __dispatch_benchmark_data_s *bdata = (struct __dispatch_benchmark_data_s *)context;
// try and simulate performance of real benchmark as much as possible
// keep 'f', 'c' and 'cnt' in registers
register void (*f)(void *) = bdata->func;
register void *c = bdata->ctxt;
register size_t cnt = bdata->count;
size_t i = 0;
uint64_t start, delta;
#if defined(__LP64__) && !defined(_MSC_VER)
__uint128_t lcost;
#else
long double lcost;
#endif
#if HAVE_MACH_ABSOLUTE_TIME
kern_return_t kr;
kr = mach_timebase_info(&bdata->tbi);
dispatch_assert_zero(kr);
#endif
start = _dispatch_absolute_time();
do {
i++;
f(c);
} while (i < cnt);
delta = _dispatch_absolute_time() - start;
lcost = (long double)delta;
#if HAVE_MACH_ABSOLUTE_TIME
lcost *= bdata->tbi.numer;
lcost /= bdata->tbi.denom;
#endif
lcost /= cnt;
bdata->loop_cost = (uint64_t)lcost;
}
