diff options
Diffstat (limited to 'benchtests/bench-skeleton.c')
-rw-r--r-- | benchtests/bench-skeleton.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/benchtests/bench-skeleton.c b/benchtests/bench-skeleton.c new file mode 100644 index 0000000000..13f986d817 --- /dev/null +++ b/benchtests/bench-skeleton.c @@ -0,0 +1,75 @@ +/* Skeleton for benchmark programs. + Copyright (C) 2013 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <string.h> +#include <stdint.h> +#include <stdio.h> +#include <time.h> +#include <inttypes.h> + +int +main (int argc, char **argv) +{ + unsigned long i, j, k; + uint64_t total = 0, max = 0, min = 0x7fffffffffffffff; + struct timespec start, end; + + memset (&start, 0, sizeof (start)); + memset (&end, 0, sizeof (end)); + + clock_getres (CLOCK_PROCESS_CPUTIME_ID, &start); + + /* Measure 1000 times the resolution of the clock. So for a 1ns resolution + clock, we measure 1000 iterations of the function call at a time. + Measurements close to the minimum clock resolution won't make much sense, + but it's better than having nothing at all. */ + unsigned long iters = 1000 * start.tv_nsec; + unsigned long total_iters = ITER / iters; + + for (i = 0; i < NUM_SAMPLES; i++) + { + for (j = 0; j < total_iters; j ++) + { + clock_gettime (CLOCK_PROCESS_CPUTIME_ID, &start); + for (k = 0; k < iters; k++) + BENCH_FUNC(i); + clock_gettime (CLOCK_PROCESS_CPUTIME_ID, &end); + + uint64_t cur = (end.tv_nsec - start.tv_nsec + + ((end.tv_sec - start.tv_sec) + * (uint64_t) 1000000000)); + + if (cur > max) + max = cur; + + if (cur < min) + min = cur; + + total += cur; + } + } + + double d_total_s = total * 1e-9; + double d_iters = iters; + double d_total_i = (double)ITER * NUM_SAMPLES; + printf (FUNCNAME ": ITERS:%g: TOTAL:%gs, MAX:%gns, MIN:%gns, %g iter/s\n", + d_total_i, d_total_s, max / d_iters, min / d_iters, + d_total_i / d_total_s); + + return 0; +} |