glibc/benchtests/bench-memccpy.c
Wilco Dijkstra 2623479105 Benchtests: Adjust timing
Adjust iteration counts so benchmarks don't run too slowly or quickly.
Ensure benchmarks take less than 10 seconds on older, slower cores and
more than 0.5 seconds on fast cores.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-04-17 13:00:38 +01:00

131 lines
3.1 KiB
C

/* Measure memccpy functions.
Copyright (C) 2013-2023 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
<https://www.gnu.org/licenses/>. */
#define TEST_MAIN
#define TEST_NAME "memccpy"
#include "bench-string.h"
void *
generic_memccpy (void *dst, const void *src, int c, size_t n)
{
void *p = memchr (src, c, n);
if (p != NULL)
return mempcpy (dst, src, p - src + 1);
memcpy (dst, src, n);
return NULL;
}
IMPL (memccpy, 1)
IMPL (generic_memccpy, 0)
typedef void *(*proto_t) (void *, const void *, int c, size_t);
static void
do_one_test (impl_t *impl, void *dst, const void *src, int c, size_t len,
size_t n)
{
size_t i, iters = INNER_LOOP_ITERS_LARGE * 4;
timing_t start, stop, cur;
TIMING_NOW (start);
for (i = 0; i < iters; ++i)
{
CALL (impl, dst, src, c, n);
}
TIMING_NOW (stop);
TIMING_DIFF (cur, start, stop);
TIMING_PRINT_MEAN ((double) cur, (double) iters);
}
static void
do_test (size_t align1, size_t align2, int c, size_t len, size_t n,
int max_char)
{
size_t i;
char *s1, *s2;
align1 &= 7;
if (align1 + len >= page_size)
return;
align2 &= 7;
if (align2 + len >= page_size)
return;
s1 = (char *) (buf1 + align1);
s2 = (char *) (buf2 + align2);
for (i = 0; i < len - 1; ++i)
{
s1[i] = 32 + 23 * i % (max_char - 32);
if (s1[i] == (char) c)
--s1[i];
}
s1[len - 1] = c;
for (i = len; i + align1 < page_size && i < len + 64; ++i)
s1[i] = 32 + 32 * i % (max_char - 32);
printf ("Length %4zd, n %4zd, char %d, alignment %2zd/%2zd:", len, n, c, align1, align2);
FOR_EACH_IMPL (impl, 0)
do_one_test (impl, s2, s1, c, len, n);
putchar ('\n');
}
int
test_main (void)
{
size_t i;
test_init ();
printf ("%28s", "");
FOR_EACH_IMPL (impl, 0)
printf ("\t%s", impl->name);
putchar ('\n');
for (i = 1; i < 8; ++i)
{
do_test (i, i, 12, 16, 16, 127);
do_test (i, i, 23, 16, 16, 255);
do_test (i, 2 * i, 28, 16, 16, 127);
do_test (2 * i, i, 31, 16, 16, 255);
do_test (8 - i, 2 * i, 1, 1 << i, 2 << i, 127);
do_test (2 * i, 8 - i, 17, 2 << i, 1 << i, 127);
do_test (8 - i, 2 * i, 0, 1 << i, 2 << i, 255);
do_test (2 * i, 8 - i, i, 2 << i, 1 << i, 255);
}
for (i = 1; i < 8; ++i)
{
do_test (0, 0, i, 4 << i, 8 << i, 127);
do_test (0, 0, i, 16 << i, 8 << i, 127);
do_test (8 - i, 2 * i, i, 4 << i, 8 << i, 127);
do_test (8 - i, 2 * i, i, 16 << i, 8 << i, 127);
}
return ret;
}
#include <support/test-driver.c>