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#include <stdio.h>
#include <time.h>
typedef long long hrtime_t;
hrtime_t
gethrtime (void)
{
struct timespec tp;
hrtime_t rc = 0;
#ifdef CLOCK_MONOTONIC_RAW
int r = clock_gettime (CLOCK_MONOTONIC_RAW, &tp);
#else
int r = clock_gettime (CLOCK_MONOTONIC, &tp);
#endif
if (r == 0)
rc = ((hrtime_t) tp.tv_sec) * 1e9 + (hrtime_t) tp.tv_nsec;
return rc;
}
volatile long x; /* temp variable for long calculation */
int
main (int argc, char **argv)
{
long long count = 0;
hrtime_t start = gethrtime ();
do
{
x = 0;
for (int j = 0; j < 1000000; j++)
x = x + 1;
count++;
}
while (start + 2e9 > gethrtime ());
printf("count=%lld x=%lld\n", count, x);
return 0;
}
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