static void analyze()
{
double xval[MAXCNT];
double yval[MAXCNT];
double slope, intercept;
double dtime;
int n;
int i;
/* Create entries */
for (i = 0; intel[i].name; i++) {
xval[i] = intel[i].year - intel[0].year;
yval[i] = log10(intel[i].trans);
}
n = i-1;
printf("Got %d values\n", n);
for (i = 0; i < n; i++)
printf("x = %f, y = %f\n", xval[i], yval[i]);
slope = ls_slope(xval, yval, n);
intercept = ls_intercept(xval, yval, n);
printf("annual growth rate = %.4f\n", pow(10, slope));
printf("intercept at year %d = %.2f\n", (int) intel[0].year, pow(10,intercept));
dtime = 0.3010/slope;
printf("Doubling time = %.2f years (%.1f months)\n", dtime, dtime*12);
for (i = 0; i < n; i++) {
printf("Year = %d, predicted %d, got %d\n",
(int) intel[i].year, (int) pow(10, intercept+xval[i]*slope),
(int) intel[i].trans);
}
exit(0);
}
/* Find absolute performance */
void find_abs_performance(double *intercept, double *slope,
int clear_cache, int verbose, int cpubench)
{
int min_param = 1;
int pcount = 10;
int i;
/* Try to get precise measurements at max_params points */
double *xval = calloc(pcount, sizeof(double));
double *yval = calloc(pcount, sizeof(double));
for (i = 0; i < pcount; i++) {
xval[i] = i+min_param;
if (cpubench)
yval[i] = fcyc_full(cpufunct, i+min_param, clear_cache, 3, 0.00000, 1000, 0);
else
yval[i] = fcyc_full(funct, i+min_param, clear_cache, 3, 0.00000, 1000, 0);
}
/* Now perform least squares fit */
*intercept = ls_intercept(xval, yval, pcount);
*slope = ls_slope(xval, yval, pcount);
if (verbose) {
double avg_err = ls_error(xval, yval, pcount, LS_AVG);
double max_err = ls_error(xval, yval, pcount, LS_MAX);
printf("Slope = %0.1f, Intercept = %.1f, max err = %f, avg err = %f\n",
*slope, *intercept, max_err, avg_err);
}
}
/* 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;
}
