#include <stdio.h>
#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>

typedef unsigned int uint32_t;
typedef unsigned long long uint64_t;

static inline uint64_t x86_get_timer(void)
{
	    uint32_t hi, lo;
		__asm__ volatile (
			"rdtsc\n"
			"mov %1, %%eax\n"
			"mov %0, %%edx\n"
			:"=r"(hi), "=r"(lo)
			:
			:"%eax", "%edx"
			);
		    return (((unsigned long long)hi) | (lo & 0xffffffff));
}

#define TO_USEC(x) ((((uint64_t)x.tv_sec) * 1e+06) + x.tv_usec)

int main(int argc, char **argv)
{
	    uint32_t i;
	    uint64_t start, stop;
#ifdef CHECK_GTD
	    struct timeval st, en;
	    uint64_t st1, en1;
#endif /* CHECK_GTD */

#ifdef CHECK_GTD
	    gettimeofday(&st, NULL);
#endif /* CHECK_GTD */
	    start = x86_get_timer();
	    printf("start=%lld\n", start);
#if 1
	    __asm__ volatile (
		    "mov $0xaea44080, %0\n"
		    "1: sub $1, %0\n"
		    "jnz 1b\n"
		    :
		    :"r"(i)
	    );
#else
	    while(--i);
#endif
	    stop = x86_get_timer();
#ifdef CHECK_GTD
	    gettimeofday(&en, NULL);
	    st1 = TO_USEC(st);
	    en1 = TO_USEC(en);
#endif /* CHECK_GTD */
	    printf("stop=%lld start=%lld diff=%lld time=%g secs\n",
		    stop, start, (stop - start),
		    (((double)(stop - start)) * 3.4129e-10));
#ifdef CHECK_GTD
	    printf("end=%lld start=%lld diff=%g secs\n",
		   en1, st1, (((double)(en1 - st1)) * 1e-06));
#endif /* CHECK_GTD */
	    return 0;

}