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#include <sys/times.h>
#include <limits.h>
#include <stdio.h>
#include <time.h>
#define CONVTYPE int
#define MAX (MIN + NITER - 1)
#define MIN INT_MIN
#define NITER 1000000
double one = 1;
double two = 2;
double big = 1e99;
double d;
double d1;
float f;
int main()
{
CONVTYPE cti;
CONVTYPE cto;
clock_t delta;
struct tms finish;
int i;
struct tms start;
#if 0
times(&start);
for (cti = MIN; cti <= MAX; ++cti)
{
d = cti;
cto = d;
if (cti != cto)
printf("%08x %08x\n", cti, cto);
if (cti % 10000000 == 0)
{
printf("%8x ok ", cti);
fflush(stdout);
}
}
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for %d i -> d and d -> i conversions was %g s (%d t)\n",
MAX - MIN + 1, delta / (double) CLOCKS_PER_SEC, delta);
#endif
times(&start);
for (cti = MIN; cti <= MAX; ++cti)
d = cti;
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for %d i -> d conversions was %g s (%d t)\n",
MAX - MIN + 1, delta / (double) CLOCKS_PER_SEC, delta);
times(&start);
for (cti = MIN; cti <= MAX; ++cti)
{
d = cti;
cto = d;
}
times(&finish);
delta = finish.tms_utime - start.tms_utime - delta;
printf("Time for %d d -> i conversions was %g s (%d t)\n",
MAX - MIN + 1, delta / (double) CLOCKS_PER_SEC, delta);
d = 0;
times(&start);
for (i = 0; i < NITER; ++i)
d = d + 1;
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for adding %d 1.0's to 0.0 was %g s (%d t), result = %g\n",
NITER, delta / (double) CLOCKS_PER_SEC, delta, d);
d = 0;
times(&start);
for (; d < NITER;)
d = d + 1;
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for adding %d 1.0's to 0.0 (d index) was %g s (%d t), result = %g\n",
NITER, delta / (double) CLOCKS_PER_SEC, delta, d);
times(&start);
for (i = 1; i <= NITER; ++i)
{
d1 = i;
d = d1 * d1;
}
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for %d mults was %g s (%d t), result = %g\n",
NITER, delta / (double) CLOCKS_PER_SEC, delta, d);
times(&start);
for (i = 1; i <= NITER; ++i)
{
d1 = i;
d = 1 / d1;
}
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for %d divs was %g s (%d t), result = %g\n",
NITER, delta / (double) CLOCKS_PER_SEC, delta, d);
f = 0;
times(&start);
for (i = 0; i < NITER; ++i)
f = f + 1;
times(&finish);
delta = finish.tms_utime - start.tms_utime;
printf("Time for adding %d 1.0f's to 0.0f was %g s (%d t), result = %g\n",
NITER, delta / (double) CLOCKS_PER_SEC, delta, f);
return 0;
}
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