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/* -*- c-file-style: "GNU" -*- */
/*
* Copyright (C) CNRS, INRIA, Université Bordeaux 1, Télécom SudParis
* See COPYING in top-level directory.
*/
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#define NB_ITER 1000000
#define SIZE 100
#define TIME_DIFF(t1, t2) ((t2.tv_sec-t1.tv_sec)*1e6+(t2.tv_usec-t1.tv_usec))
double foo_compute(int n, double* a, double*b, double*c) {
double res = 0;
int i;
for (i = 0; i < n; i++) {
c[i] = a[i] + b[i];
res += c[i];
}
return res;
}
int main() {
int i;
double res = 0;
struct timeval t1, t2;
double *a, *b, *c;
a = malloc(sizeof(double) * SIZE);
b = malloc(sizeof(double) * SIZE);
c = malloc(sizeof(double) * SIZE);
for (i = 0; i < SIZE; i++) {
a[i] = i;
b[i] = i;
}
printf("START !\n");
if (gettimeofday(&t1, NULL)) {
perror("gettimeofday");
}
for (i = 0; i < NB_ITER; i++) {
res += foo_compute(SIZE, a, b, c);
}
/* fin de la mesure */
if (gettimeofday(&t2, NULL)) {
perror("gettimeofday");
}
printf("STOP !\n");
/* affichage du resultat */
printf("res = %lf\n", res);
printf("%d iterations in %lf s (%lf µs per iteration)\n", NB_ITER,
TIME_DIFF(t1, t2) / 1e6, TIME_DIFF(t1, t2) / NB_ITER);
return 0;
}
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