glibc/benchtests/bench-strchr.c
Anton Youdkevitch afe23eb0f1 Bump up the runtime for "short" benchmarks
Some benchmarks with a very short runtime show significantly
different results across runs on Aarch64 - up to tens of percents.
Increasing the runtime to 100ms+ makes the deviation under 5%.

Tested on Aarch64 and x86-64.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

	* benchtests/bench-memccpy.c: Replace INNER_LOOP_ITERS
	with INNER_LOOP_ITERS_LARGE.
	* benchtests/bench-memchr.c: Likewise.
	* benchtests/bench-rawmemchr.c: Likewise.
	* benchtests/bench-strcat.c: Likewise.
	* benchtests/bench-strchr.c: Likewise.
	* benchtests/bench-string.h: Likewise.
	* benchtests/bench-strlen.c: Likewise.
	* benchtests/bench-strncpy.c: Likewise.
	* benchtests/bench-strnlen.c: Likewise.
2019-06-28 13:38:07 +01:00

188 lines
4.3 KiB
C

/* Measure STRCHR functions.
Copyright (C) 2013-2019 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/>. */
#define TEST_MAIN
#ifndef WIDE
# ifdef USE_FOR_STRCHRNUL
# define TEST_NAME "strchrnul"
# else
# define TEST_NAME "strchr"
# endif /* !USE_FOR_STRCHRNUL */
#else
# ifdef USE_FOR_STRCHRNUL
# define TEST_NAME "wcschrnul"
# else
# define TEST_NAME "wcschr"
# endif /* !USE_FOR_STRCHRNUL */
#endif /* WIDE */
#include "bench-string.h"
#define BIG_CHAR MAX_CHAR
#ifndef WIDE
# ifdef USE_FOR_STRCHRNUL
# undef STRCHR
# define STRCHR strchrnul
# define simple_STRCHR simple_STRCHRNUL
# endif /* !USE_FOR_STRCHRNUL */
# define MIDDLE_CHAR 127
# define SMALL_CHAR 23
#else
# ifdef USE_FOR_STRCHRNUL
# undef STRCHR
# define STRCHR wcschrnul
# define simple_STRCHR simple_WCSCHRNUL
# endif /* !USE_FOR_STRCHRNUL */
# define MIDDLE_CHAR 1121
# define SMALL_CHAR 851
#endif /* WIDE */
#ifdef USE_FOR_STRCHRNUL
# define NULLRET(endptr) endptr
#else
# define NULLRET(endptr) NULL
#endif /* !USE_FOR_STRCHRNUL */
typedef CHAR *(*proto_t) (const CHAR *, int);
CHAR *
simple_STRCHR (const CHAR *s, int c)
{
for (; *s != (CHAR) c; ++s)
if (*s == '\0')
return NULLRET ((CHAR *) s);
return (CHAR *) s;
}
IMPL (simple_STRCHR, 0)
IMPL (STRCHR, 1)
static void
do_one_test (impl_t *impl, const CHAR *s, int c, const CHAR *exp_res)
{
size_t i, iters = INNER_LOOP_ITERS_LARGE;
timing_t start, stop, cur;
TIMING_NOW (start);
for (i = 0; i < iters; ++i)
{
CALL (impl, s, c);
}
TIMING_NOW (stop);
TIMING_DIFF (cur, start, stop);
TIMING_PRINT_MEAN ((double) cur, (double) iters);
}
static void
do_test (size_t align, size_t pos, size_t len, int seek_char, int max_char)
/* For wcschr: align here means align not in bytes,
but in wchar_ts, in bytes it will equal to align * (sizeof (wchar_t))
len for wcschr here isn't in bytes but it's number of wchar_t symbols. */
{
size_t i;
CHAR *result;
CHAR *buf = (CHAR *) buf1;
align &= 15;
if ((align + len) * sizeof (CHAR) >= page_size)
return;
for (i = 0; i < len; ++i)
{
buf[align + i] = 32 + 23 * i % max_char;
if (buf[align + i] == seek_char)
buf[align + i] = seek_char + 1;
else if (buf[align + i] == 0)
buf[align + i] = 1;
}
buf[align + len] = 0;
if (pos < len)
{
buf[align + pos] = seek_char;
result = buf + align + pos;
}
else if (seek_char == 0)
result = buf + align + len;
else
result = NULLRET (buf + align + len);
printf ("Length %4zd, alignment in bytes %2zd:",
pos, align * sizeof (CHAR));
FOR_EACH_IMPL (impl, 0)
do_one_test (impl, buf + align, seek_char, result);
putchar ('\n');
}
int
test_main (void)
{
size_t i;
test_init ();
printf ("%20s", "");
FOR_EACH_IMPL (impl, 0)
printf ("\t%s", impl->name);
putchar ('\n');
for (i = 1; i < 8; ++i)
{
do_test (0, 16 << i, 2048, SMALL_CHAR, MIDDLE_CHAR);
do_test (i, 16 << i, 2048, SMALL_CHAR, MIDDLE_CHAR);
}
for (i = 1; i < 8; ++i)
{
do_test (i, 64, 256, SMALL_CHAR, MIDDLE_CHAR);
do_test (i, 64, 256, SMALL_CHAR, BIG_CHAR);
}
for (i = 0; i < 32; ++i)
{
do_test (0, i, i + 1, SMALL_CHAR, MIDDLE_CHAR);
do_test (0, i, i + 1, SMALL_CHAR, BIG_CHAR);
}
for (i = 1; i < 8; ++i)
{
do_test (0, 16 << i, 2048, 0, MIDDLE_CHAR);
do_test (i, 16 << i, 2048, 0, MIDDLE_CHAR);
}
for (i = 1; i < 8; ++i)
{
do_test (i, 64, 256, 0, MIDDLE_CHAR);
do_test (i, 64, 256, 0, BIG_CHAR);
}
for (i = 0; i < 32; ++i)
{
do_test (0, i, i + 1, 0, MIDDLE_CHAR);
do_test (0, i, i + 1, 0, BIG_CHAR);
}
return ret;
}
#include <support/test-driver.c>