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/* Measure strncmp functions.
Copyright (C) 2013-2015 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
#define TEST_NAME "strncmp"
#include "bench-string.h"
typedef int (*proto_t) (const char *, const char *, size_t);
int simple_strncmp (const char *, const char *, size_t);
int stupid_strncmp (const char *, const char *, size_t);
IMPL (stupid_strncmp, 0)
IMPL (simple_strncmp, 0)
IMPL (strncmp, 1)
int
simple_strncmp (const char *s1, const char *s2, size_t n)
{
int ret = 0;
while (n-- && (ret = *(unsigned char *) s1 - * (unsigned char *) s2++) == 0
&& *s1++);
return ret;
}
int
stupid_strncmp (const char *s1, const char *s2, size_t n)
{
size_t ns1 = strnlen (s1, n) + 1, ns2 = strnlen (s2, n) + 1;
int ret = 0;
n = ns1 < n ? ns1 : n;
n = ns2 < n ? ns2 : n;
while (n-- && (ret = *(unsigned char *) s1++ - * (unsigned char *) s2++) == 0);
return ret;
}
static void
do_one_test (impl_t *impl, const char *s1, const char *s2, size_t n,
int exp_result)
{
size_t i, iters = INNER_LOOP_ITERS;
timing_t start, stop, cur;
TIMING_NOW (start);
for (i = 0; i < iters; ++i)
{
CALL (impl, s1, s2, n);
}
TIMING_NOW (stop);
TIMING_DIFF (cur, start, stop);
TIMING_PRINT_MEAN ((double) cur, (double) iters);
}
static void
do_test_limit (size_t align1, size_t align2, size_t len, size_t n, int max_char,
int exp_result)
{
size_t i, align_n;
char *s1, *s2;
if (n == 0)
{
s1 = (char*)(buf1 + page_size);
s2 = (char*)(buf2 + page_size);
printf ("Length %4zd/%4zd:", len, n);
FOR_EACH_IMPL (impl, 0)
do_one_test (impl, s1, s2, n, 0);
putchar ('\n');
return;
}
align1 &= 15;
align2 &= 15;
align_n = (page_size - n) & 15;
s1 = (char*)(buf1 + page_size - n);
s2 = (char*)(buf2 + page_size - n);
if (align1 < align_n)
s1 -= (align_n - align1);
if (align2 < align_n)
s2 -= (align_n - align2);
for (i = 0; i < n; i++)
s1[i] = s2[i] = 1 + 23 * i % max_char;
if (len < n)
{
s1[len] = 0;
s2[len] = 0;
if (exp_result < 0)
s2[len] = 32;
else if (exp_result > 0)
s1[len] = 64;
}
printf ("Length %4zd/%4zd, alignment %2zd/%2zd:", len, n, align1, align2);
FOR_EACH_IMPL (impl, 0)
do_one_test (impl, s1, s2, n, exp_result);
putchar ('\n');
}
static void
do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char,
int exp_result)
{
size_t i;
char *s1, *s2;
if (n == 0)
return;
align1 &= 7;
if (align1 + n + 1 >= page_size)
return;
align2 &= 7;
if (align2 + n + 1 >= page_size)
return;
s1 = (char*)(buf1 + align1);
s2 = (char*)(buf2 + align2);
for (i = 0; i < n; i++)
s1[i] = s2[i] = 1 + 23 * i % max_char;
s1[n] = 24 + exp_result;
s2[n] = 23;
s1[len] = 0;
s2[len] = 0;
if (exp_result < 0)
s2[len] = 32;
else if (exp_result > 0)
s1[len] = 64;
if (len >= n)
s2[n - 1] -= exp_result;
printf ("Length %4zd/%4zd, alignment %2zd/%2zd:", len, n, align1, align2);
FOR_EACH_IMPL (impl, 0)
do_one_test (impl, (char*)s1, (char*)s2, n, exp_result);
putchar ('\n');
}
int
test_main (void)
{
size_t i;
test_init ();
printf ("%23s", "");
FOR_EACH_IMPL (impl, 0)
printf ("\t%s", impl->name);
putchar ('\n');
for (i =0; i < 16; ++i)
{
do_test (0, 0, 8, i, 127, 0);
do_test (0, 0, 8, i, 127, -1);
do_test (0, 0, 8, i, 127, 1);
do_test (i, i, 8, i, 127, 0);
do_test (i, i, 8, i, 127, 1);
do_test (i, i, 8, i, 127, -1);
do_test (i, 2 * i, 8, i, 127, 0);
do_test (2 * i, i, 8, i, 127, 1);
do_test (i, 3 * i, 8, i, 127, -1);
do_test (0, 0, 8, i, 255, 0);
do_test (0, 0, 8, i, 255, -1);
do_test (0, 0, 8, i, 255, 1);
do_test (i, i, 8, i, 255, 0);
do_test (i, i, 8, i, 255, 1);
do_test (i, i, 8, i, 255, -1);
do_test (i, 2 * i, 8, i, 255, 0);
do_test (2 * i, i, 8, i, 255, 1);
do_test (i, 3 * i, 8, i, 255, -1);
}
for (i = 1; i < 8; ++i)
{
do_test (0, 0, 8 << i, 16 << i, 127, 0);
do_test (0, 0, 8 << i, 16 << i, 127, 1);
do_test (0, 0, 8 << i, 16 << i, 127, -1);
do_test (0, 0, 8 << i, 16 << i, 255, 0);
do_test (0, 0, 8 << i, 16 << i, 255, 1);
do_test (0, 0, 8 << i, 16 << i, 255, -1);
do_test (8 - i, 2 * i, 8 << i, 16 << i, 127, 0);
do_test (8 - i, 2 * i, 8 << i, 16 << i, 127, 1);
do_test (2 * i, i, 8 << i, 16 << i, 255, 0);
do_test (2 * i, i, 8 << i, 16 << i, 255, 1);
}
do_test_limit (0, 0, 0, 0, 127, 0);
do_test_limit (4, 0, 21, 20, 127, 0);
do_test_limit (0, 4, 21, 20, 127, 0);
do_test_limit (8, 0, 25, 24, 127, 0);
do_test_limit (0, 8, 25, 24, 127, 0);
for (i = 0; i < 8; ++i)
{
do_test_limit (0, 0, 17 - i, 16 - i, 127, 0);
do_test_limit (0, 0, 17 - i, 16 - i, 255, 0);
do_test_limit (0, 0, 15 - i, 16 - i, 127, 0);
do_test_limit (0, 0, 15 - i, 16 - i, 127, 1);
do_test_limit (0, 0, 15 - i, 16 - i, 127, -1);
do_test_limit (0, 0, 15 - i, 16 - i, 255, 0);
do_test_limit (0, 0, 15 - i, 16 - i, 255, 1);
do_test_limit (0, 0, 15 - i, 16 - i, 255, -1);
}
return ret;
}
#include "../test-skeleton.c"
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