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/* -*- c-file-style: "GNU" -*- */
/*
* Copyright (C) CNRS, INRIA, Université Bordeaux 1, Télécom SudParis
* See COPYING in top-level directory.
*/
/* simple program that calls the libexample library */
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <assert.h>
#include "example.h"
#define NITER 100000
#define ARRAY_SIZE (1024*1024)
#define TIME_DIFF(t1, t2) \
((t2.tv_sec - t1.tv_sec) * 1e9 + (t2.tv_nsec - t1.tv_nsec))
int bin_function(double *t, int size, int n) {
int res = n;
int i;
for(i=0; i<NITER_COMPUTE; i++) {
res +=(int) t[(i*n)%size];
}
return res;
}
int bin_instrumented_function(double *t, int size, int n) {
int res = n;
int i;
for(i=0; i<NITER_COMPUTE; i++) {
res +=(int) t[(i*n)%size];
}
return res;
}
double *t = NULL;
int size;
double benchmark_function(int (*function)(double*, int, int),
int (*instrumented_function)(double*, int, int),
const char* fname) {
struct timespec t1, t2;
struct timespec ti1, ti2;
int i;
int res = 0;
printf("Benchmarking %s\n", fname);
printf("---------------\n");
/* Run the instrumented function */
printf("Running the instrumented function...\n");
int resi = 0;
clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ti1);
for(i=0; i<NITER; i++) {
resi += instrumented_function(t, size, i);
}
clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ti2);
printf("resi = %d\n", resi);
double duration_i = TIME_DIFF(ti1, ti2);
printf("%d iterations in %lf ms (%lf ns per function call)\n", NITER, duration_i/1e6, duration_i/NITER);
/* Run the non-instrumented function */
printf("Running the non-instrumented function...\n");
clock_gettime(CLOCK_THREAD_CPUTIME_ID, &t1);
for(i=0; i<NITER; i++) {
res += function(t, size, i);
}
clock_gettime(CLOCK_THREAD_CPUTIME_ID, &t2);
printf("res = %d\n", res);
double duration = TIME_DIFF(t1, t2);
printf("%d iterations in %lf ms (%lf ns per function call)\n", NITER, duration/1e6, duration/NITER);
/* Print the result */
assert(res == resi);
double duration_diff = duration_i - duration;
printf("overhead: %lf ms (%lf ns per function call)\n", duration_diff/1e6, duration_diff/NITER);
return duration_diff/NITER;
}
void init() {
size = ARRAY_SIZE;
t = malloc(sizeof(double)*size);
int i;
for(i=0; i<size; i++) {
t[i] = (i*(i*17))%size;
}
}
int main(int argc, char**argv) {
int i;
init();
double diff[10][2];
double total_diff[2] = {0, 0};
for(i=0; i<10; i++) {
diff[i][0] = benchmark_function(bin_function, bin_instrumented_function, "bin_function");
total_diff[0] += diff[i][0];
//diff[i][1] = benchmark_function(lib_function, lib_instrumented_function, "lib_function");
//total_diff[1] += diff[i][1];
}
printf("\n\nSummary:\n");
printf("Average diff for bin: %lf ns\n", total_diff[0]/10);
printf("Average diff for lib: %lf ns\n", total_diff[1]/10);
return 0;
}
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