#include <stdint.h>
#include <stdio.h>
#include <pthread.h>
static uint64_t  __attribute__((noinline)) rdtsc(void)
{
  uint32_t lo, hi;
  __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
  return (uint64_t)hi << 32 | lo;
}

uint64_t x;
char y[100];

void fn(void *x)
{
  int i = 0;
  while (1)
    {
      y[(i%100)] = 42;
      i++;
    }
}

int main()
{
  x = 0;
  int i;
  int times=10000000;
  pthread_t thread;
#ifdef THREAD
 pthread_create (&thread, NULL, (void *) &fn, NULL);
#endif
  uint64_t start = rdtsc();
  for (i=0;i<times;i++)
   {
     __sync_bool_compare_and_swap (&x,i,i+1);
   }
  uint64_t end = rdtsc();
  printf ("%lli\n", (end-start)/times);
}