benchtests/bench-strncat.c

   1 /* Measure strncat functions.
   2    Copyright (C) 2013 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #define TEST_MAIN
  20 #define TEST_NAME "strncat"
  21 #include "bench-string.h"
  22
  23 typedef char *(*proto_t) (char *, const char *, size_t);
  24 char *stupid_strncat (char *, const char *, size_t);
  25 char *simple_strncat (char *, const char *, size_t);
  26
  27 IMPL (stupid_strncat, 0)
  28 IMPL (strncat, 2)
  29
  30 char *
  31 stupid_strncat (char *dst, const char *src, size_t n)
  32 {
  33   char *ret = dst;
  34   while (*dst++ != '\0');
  35   --dst;
  36   while (n--)
  37     if ( (*dst++ = *src++) == '\0')
  38       return ret;
  39   *dst = '\0';
  40   return ret;
  41 }
  42
  43 static void
  44 do_one_test (impl_t *impl, char *dst, const char *src, size_t n)
  45 {
  46   size_t k = strlen (dst);
  47   if (CALL (impl, dst, src, n) != dst)
  48     {
  49       error (0, 0, "Wrong result in function %s %p != %p", impl->name,
  50              CALL (impl, dst, src, n), dst);
  51       ret = 1;
  52       return;
  53     }
  54
  55   size_t len = strlen (src);
  56   if (memcmp (dst + k, src, len + 1 > n ? n : len + 1) != 0)
  57     {
  58       error (0, 0, "Incorrect cancatination in function %s",
  59              impl->name);
  60       ret = 1;
  61       return;
  62     }
  63   if (n < len && dst[k + n] != '\0')
  64     {
  65       error (0, 0, "There is no zero in the end of output string in %s",
  66              impl->name);
  67       ret = 1;
  68       return;
  69     }
  70   if (HP_TIMING_AVAIL)
  71     {
  72       hp_timing_t start __attribute ((unused));
  73       hp_timing_t stop __attribute ((unused));
  74       hp_timing_t best_time = ~ (hp_timing_t) 0;
  75       size_t i;
  76
  77       for (i = 0; i < 32; ++i)
  78         {
  79           dst[k] = '\0';
  80           HP_TIMING_NOW (start);
  81           CALL (impl, dst, src, n);
  82           HP_TIMING_NOW (stop);
  83           HP_TIMING_BEST (best_time, start, stop);
  84         }
  85
  86       printf ("\t%zd", (size_t) best_time);
  87     }
  88 }
  89
  90 static void
  91 do_test (size_t align1, size_t align2, size_t len1, size_t len2,
  92          size_t n, int max_char)
  93 {
  94   size_t i;
  95   char *s1, *s2;
  96
  97   align1 &= 7;
  98   if (align1 + len1 >= page_size)
  99     return;
 100   if (align1 + n > page_size)
 101     return;
 102   align2 &= 7;
 103   if (align2 + len1 + len2 >= page_size)
 104     return;
 105   if (align2 + len1 + n > page_size)
 106     return;
 107   s1 = (char *) (buf1 + align1);
 108   s2 = (char *) (buf2 + align2);
 109
 110   for (i = 0; i < len1; ++i)
 111     s1[i] = 32 + 23 * i % (max_char - 32);
 112   s1[len1] = '\0';
 113
 114   for (i = 0; i < len2; i++)
 115     s2[i] = 32 + 23 * i % (max_char - 32);
 116
 117   if (HP_TIMING_AVAIL)
 118     printf ("Length %4zd/%4zd, alignment %2zd/%2zd, N %4zd:",
 119             len1, len2, align1, align2, n);
 120
 121   FOR_EACH_IMPL (impl, 0)
 122     {
 123       s2[len2] = '\0';
 124       do_one_test (impl, s2, s1, n);
 125     }
 126
 127   if (HP_TIMING_AVAIL)
 128     putchar ('\n');
 129 }
 130
 131 int
 132 main (void)
 133 {
 134   size_t i, n;
 135
 136   test_init ();
 137
 138   printf ("%28s", "");
 139   FOR_EACH_IMPL (impl, 0)
 140     printf ("\t%s", impl->name);
 141   putchar ('\n');
 142
 143   for (n = 2; n <= 2048; n*=4)
 144     {
 145       do_test (0, 2, 2, 2, n, 127);
 146       do_test (0, 0, 4, 4, n, 127);
 147       do_test (4, 0, 4, 4, n, 255);
 148       do_test (0, 0, 8, 8, n, 127);
 149       do_test (0, 8, 8, 8, n, 127);
 150
 151       for (i = 1; i < 8; ++i)
 152         {
 153           do_test (0, 0, 8 << i, 8 << i, n, 127);
 154           do_test (8 - i, 2 * i, 8 << i, 8 << i, n, 127);
 155           do_test (0, 0, 8 << i, 2 << i, n, 127);
 156           do_test (8 - i, 2 * i, 8 << i, 2 << i, n, 127);
 157         }
 158
 159       for (i = 1; i < 8; ++i)
 160         {
 161           do_test (i, 2 * i, 8 << i, 1, n, 127);
 162           do_test (2 * i, i, 8 << i, 1, n, 255);
 163           do_test (i, i, 8 << i, 10, n, 127);
 164         }
 165     }
 166
 167   return ret;
 168 }