glibc/benchtests/bench-memchr.c
Noah Goldstein d0370d992e Benchtests: Improve memrchr benchmarks
Add a second iteration for memrchr to set `pos` starting from the end
of the buffer.

Previously `pos` was only set relative to the beginning of the
buffer. This isn't really useful for memrchr because the beginning
of the search space is (buf + len).
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-06-07 13:09:16 -07:00

224 lines
6.2 KiB
C

/* Measure memchr functions.
Copyright (C) 2013-2022 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/>. */
#ifndef WIDE
# define SMALL_CHAR 127
#else
# define SMALL_CHAR 1273
#endif /* WIDE */
#ifndef USE_AS_MEMRCHR
# define TEST_MAIN
# ifndef WIDE
# define TEST_NAME "memchr"
# else
# define TEST_NAME "wmemchr"
# endif /* WIDE */
# include "bench-string.h"
# ifndef WIDE
# define SIMPLE_MEMCHR simple_memchr
# else
# define SIMPLE_MEMCHR simple_wmemchr
# endif /* WIDE */
typedef CHAR *(*proto_t) (const CHAR *, int, size_t);
CHAR *SIMPLE_MEMCHR (const CHAR *, int, size_t);
IMPL (SIMPLE_MEMCHR, 0)
IMPL (MEMCHR, 1)
CHAR *
SIMPLE_MEMCHR (const CHAR *s, int c, size_t n)
{
while (n--)
if (*s++ == (CHAR) c)
return (CHAR *) s - 1;
return NULL;
}
#endif /* !USE_AS_MEMRCHR */
#include "json-lib.h"
static void
do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s, int c,
size_t n)
{
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, n);
}
TIMING_NOW (stop);
TIMING_DIFF (cur, start, stop);
json_element_double (json_ctx, (double) cur / (double) iters);
}
static void
do_test (json_ctx_t *json_ctx, size_t align, size_t pos, size_t len,
int seek_char, int invert_pos)
{
size_t i;
align &= getpagesize () - 1;
if ((align + len) * sizeof (CHAR) >= page_size)
return;
CHAR *buf = (CHAR *) (buf1);
for (i = 0; i < len; ++i)
{
buf[align + i] = 1 + 23 * i % SMALL_CHAR;
if (buf[align + i] == seek_char)
buf[align + i] = seek_char + 1;
}
buf[align + len] = 0;
if (pos < len)
{
if (invert_pos)
buf[align + len - pos] = seek_char;
else
buf[align + pos] = seek_char;
buf[align + len] = -seek_char;
}
else
{
buf[align + len] = seek_char;
}
json_element_object_begin (json_ctx);
json_attr_uint (json_ctx, "align", align);
json_attr_uint (json_ctx, "pos", pos);
json_attr_uint (json_ctx, "len", len);
json_attr_uint (json_ctx, "seek_char", seek_char);
json_attr_uint (json_ctx, "invert_pos", invert_pos);
json_array_begin (json_ctx, "timings");
FOR_EACH_IMPL (impl, 0)
do_one_test (json_ctx, impl, (CHAR *) (buf + align), seek_char, len);
json_array_end (json_ctx);
json_element_object_end (json_ctx);
}
int
test_main (void)
{
size_t i;
int repeats;
json_ctx_t json_ctx;
test_init ();
json_init (&json_ctx, 0, stdout);
json_document_begin (&json_ctx);
json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
json_attr_object_begin (&json_ctx, "functions");
json_attr_object_begin (&json_ctx, TEST_NAME);
json_attr_string (&json_ctx, "bench-variant", "");
json_array_begin (&json_ctx, "ifuncs");
FOR_EACH_IMPL (impl, 0)
json_element_string (&json_ctx, impl->name);
json_array_end (&json_ctx);
json_array_begin (&json_ctx, "results");
for (repeats = 0; repeats < 2; ++repeats)
{
for (i = 1; i < 8; ++i)
{
do_test (&json_ctx, 0, 16 << i, 2048, 23, repeats);
do_test (&json_ctx, i, 64, 256, 23, repeats);
do_test (&json_ctx, 0, 16 << i, 2048, 0, repeats);
do_test (&json_ctx, i, 64, 256, 0, repeats);
do_test (&json_ctx, getpagesize () - 15, 64, 256, 0, repeats);
#ifdef USE_AS_MEMRCHR
/* Also test the position close to the beginning for memrchr. */
do_test (&json_ctx, 0, i, 256, 23, repeats);
do_test (&json_ctx, 0, i, 256, 0, repeats);
do_test (&json_ctx, i, i, 256, 23, repeats);
do_test (&json_ctx, i, i, 256, 0, repeats);
#endif
}
for (i = 1; i < 8; ++i)
{
do_test (&json_ctx, i, i << 5, 192, 23, repeats);
do_test (&json_ctx, i, i << 5, 192, 0, repeats);
do_test (&json_ctx, i, i << 5, 256, 23, repeats);
do_test (&json_ctx, i, i << 5, 256, 0, repeats);
do_test (&json_ctx, i, i << 5, 512, 23, repeats);
do_test (&json_ctx, i, i << 5, 512, 0, repeats);
do_test (&json_ctx, getpagesize () - 15, i << 5, 256, 23, repeats);
}
for (i = 1; i < 32; ++i)
{
do_test (&json_ctx, 0, i, i + 1, 23, repeats);
do_test (&json_ctx, 0, i, i + 1, 0, repeats);
do_test (&json_ctx, i, i, i + 1, 23, repeats);
do_test (&json_ctx, i, i, i + 1, 0, repeats);
do_test (&json_ctx, 0, i, i - 1, 23, repeats);
do_test (&json_ctx, 0, i, i - 1, 0, repeats);
do_test (&json_ctx, i, i, i - 1, 23, repeats);
do_test (&json_ctx, i, i, i - 1, 0, repeats);
do_test (&json_ctx, getpagesize () / 2, i, i + 1, 23, repeats);
do_test (&json_ctx, getpagesize () / 2, i, i + 1, 0, repeats);
do_test (&json_ctx, getpagesize () / 2 + i, i, i + 1, 23, repeats);
do_test (&json_ctx, getpagesize () / 2 + i, i, i + 1, 0, repeats);
do_test (&json_ctx, getpagesize () / 2, i, i - 1, 23, repeats);
do_test (&json_ctx, getpagesize () / 2, i, i - 1, 0, repeats);
do_test (&json_ctx, getpagesize () / 2 + i, i, i - 1, 23, repeats);
do_test (&json_ctx, getpagesize () / 2 + i, i, i - 1, 0, repeats);
do_test (&json_ctx, getpagesize () - 15, i, i - 1, 23, repeats);
do_test (&json_ctx, getpagesize () - 15, i, i - 1, 0, repeats);
do_test (&json_ctx, getpagesize () - 15, i, i + 1, 23, repeats);
do_test (&json_ctx, getpagesize () - 15, i, i + 1, 0, repeats);
#ifdef USE_AS_MEMRCHR
do_test (&json_ctx, 0, 1, i + 1, 23, repeats);
do_test (&json_ctx, 0, 2, i + 1, 0, repeats);
#endif
}
#ifndef USE_AS_MEMRCHR
break;
#endif
}
json_array_end (&json_ctx);
json_attr_object_end (&json_ctx);
json_attr_object_end (&json_ctx);
json_document_end (&json_ctx);
return ret;
}
#include <support/test-driver.c>