main.c

// INCLUDES --------------------------------------------------------------------
#include <stdlib.h>
#include <stdio.h>
#include <sys/time.h>
#include <time.h>

// DEFINES ---------------------------------------------------------------------
#define MAXDIM 500
#define STEP 1
#define NUMTHREADS 8
#define RUNS 10

// VARIABLES -------------------------------------------------------------------
int matrix_a[MAXDIM][MAXDIM], matrix_b[MAXDIM][MAXDIM];
int matrix_c[MAXDIM][MAXDIM];
int dim;
int threads;

// MATRIX FUNCTIONS ------------------------------------------------------------
void print_matrix(int matrix[][MAXDIM]) {
    for (int r = 0; r < dim; r++) {
        for (int c = 0; c < dim; c++)
            printf("%7d ", matrix[r][c]);
        printf("\n");
    }
    printf("\n");
}

void random_matrix(int matrix[][MAXDIM]) {
    for (int r = 0; r < dim; r++)
        for (int c = 0; c < dim; c++)
            matrix[r][c] = rand() % 100;
}


float run(void (*f)()) {
    float time = 0;

    for (int i = 0; i < RUNS; i++) {
        struct timeval start, end;
        gettimeofday(&start, NULL);
        (*f)();
        gettimeofday(&end, NULL);

        long s = start.tv_sec * 1000 + start.tv_usec / 1000;
        long e = end.tv_sec * 1000 + end.tv_usec / 1000;

        time += e - s;
    }
    return time / RUNS;
}

// SEQ MULTIPLICATION ----------------------------------------------------------
void mult_seq() {
    for (int r = 0; r < dim; r++) {
        for (int c = 0; c < dim; c++) {
            matrix_c[r][c] = 0;
            for (int i = 0; i < dim; i++)
                matrix_c[r][c] += matrix_a[r][i] * matrix_b[i][c];
        }
    }
}

// MAIN ------------------------------------------------------------------------
int main(int argc, char* argv[]) {
    srand(time(NULL));

    dim = 512;
    random_matrix(matrix_a);
    random_matrix(matrix_b);
    printf("%d ", dim);
    printf("%f \n", run(mult_seq));
    return 0;
}