/* Find cpe for function f, which allows cnt up to maxcnt, using
specified number of sample points.
If data_file, then print data so that can plot points with Excel
smethod determines method for generating samples
*/
double find_cpe_full(elem_fun_t f, int maxcnt, int samples, FILE *data_file,
sample_t smethod, double bias, int verbose)
{
int i;
int cnt;
double cpe;
double overhead = 0.0;
double *cnt_val = calloc(samples, sizeof(double));
double *cycle_val = calloc(samples, sizeof(double));
/* Do the samples */
srandom(SEED);
for (i = 0; i < samples; i++) {
cnt = get_cnt(i, samples, maxcnt, smethod, bias);
cnt_val[i] = cnt;
cycle_val[i] = measure_function(f, cnt);
}
/* Fit data */
cpe = ls_slope(cnt_val, cycle_val, samples);
if (data_file)
overhead = ls_intercept(cnt_val, cycle_val, samples);
if (data_file && verbose) {
/* Print x values */
fprintf(data_file, "Cnt\t0");
for (i = 0; i < samples; i++)
fprintf(data_file, "\t%.0f", cnt_val[i]);
fprintf(data_file, "\n");
/* Print y values */
fprintf(data_file, "Cycs.\t");
for (i = 0; i < samples; i++)
fprintf(data_file, "\t%.2f", cycle_val[i]);
fprintf(data_file, "\n");
#if 0
/* Print (y-b)/x values */
fprintf(data_file, "CPE");
for (i = 0; i < samples; i++)
fprintf(data_file, "\t%.2f", (cycle_val[i]-overhead)/cnt_val[i]);
fprintf(data_file, "\n");
#endif
/* Print ax*b values */
fprintf(data_file, "Interp.\t%.2f", overhead);
for (i = 0; i < samples; i++)
fprintf(data_file, "\t%.2f", cpe*cnt_val[i]+overhead);
fprintf(data_file, "\n");
}
if (data_file && verbose) {
/* Print results */
fprintf(data_file, "cpe\t%.2f\tovhd\t%.2f\tavgerr\t\%.3f\tmaxerr\t\%.3f\n",
cpe, overhead,
ls_error(cnt_val, cycle_val, samples, LS_AVG),
ls_error(cnt_val, cycle_val, samples, LS_MAX));
}
free(cnt_val);
free(cycle_val);
return cpe;
}
/* Test and measure polynomial evaluation function. Set values
of CPE and CFIX */
void run_poly(peval_fun f, char *descr, double *cpep, double *cfixp)
{
pfun = f;
printf("Function %s\n", descr);
if (test_poly(f, stdout)) {
double cpe =
find_cpe_full(run_fun, test_degree, 300,
stdout, RAN_SAMPLE, 0.2, 0);
double fix_time = measure_function(run_fun, FIXDEGREE);
if (verbose)
printf(" CPE = %.2f\tOverhead = %.2f\tC(%d) = %.1f\n", cpe,
last_overhead, FIXDEGREE, fix_time);
else
printf(" CPE = %.2f\tC(%d) = %.1f\n", cpe,
FIXDEGREE, fix_time);
if (cpep)
*cpep = cpe;
if (cfixp)
*cfixp = fix_time;
}
}
int main(int argc, char *argv[])
{
elem_fun_t f = tpsum1;
int cnt = 1024;
int i;
int samples = 8;
double bias = 0.0;
int reps = 1;
int seed = 31415;
int verbose = 2;
sample_t smethod = UNI_SAMPLE;
for (i = 1; i < argc; i++) {
if (*argv[i] == '-')
switch(argv[i][1]) {
case 'u':
f = tpsum2;
break;
case 'a':
f = tpsum1a;
break;
case 'r':
smethod = RAN_SAMPLE;
break;
case 'q':
verbose = 0;
break;
case 'l':
i++;
if (i >= argc)
usage(argv[0]);
cnt = atoi(argv[i]);
if (cnt <= 0 || cnt > MAXCNT)
usage(argv[0]);
break;
case 'n':
i++;
if (i >= argc)
usage(argv[0]);
reps = atoi(argv[i]);
if (reps < 0)
usage(argv[0]);
break;
case 'k':
i++;
if (i >= argc)
usage(argv[0]);
seed = atoi(argv[i]);
break;
case 'b':
i++;
if (i >= argc)
usage(argv[0]);
bias = atof(argv[i]);
if (bias < 0 || bias > 1.0)
usage(argv[0]);
break;
case 's':
i++;
if (i >= argc)
usage(argv[0]);
samples = atoi(argv[i]);
if (samples <= 0)
usage(argv[0]);
break;
default:
usage(argv[0]);
break;
}
}
setup(cnt);
if (f != tpsum1)
check(f, cnt);
if (samples == 1) {
double t = measure_function(f, cnt);
printf("Cycles = %.2f, CPE = %.2f\n",
t, t/cnt);
} else {
double cpe_full, cpe_def;
while (reps--) {
srandom(seed);
cpe_full = find_cpe_full(f, cnt, samples, stdout, smethod, bias, verbose);
printf("Full cpe = %.2f\n", cpe_full);
}
cpe_def = find_cpe(f, cnt);
printf("Default cpe = %.2f\n", cpe_def);
}
return 0;
}
