benchtests/bench-strncpy.c

   1 /* Measure strncpy 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 #ifndef STRNCPY_RESULT
  20 # define STRNCPY_RESULT(dst, len, n) dst
  21 # define TEST_MAIN
  22 # define TEST_NAME "strncpy"
  23 # include "bench-string.h"
  24
  25 char *simple_strncpy (char *, const char *, size_t);
  26 char *stupid_strncpy (char *, const char *, size_t);
  27
  28 IMPL (stupid_strncpy, 0)
  29 IMPL (simple_strncpy, 0)
  30 IMPL (strncpy, 1)
  31
  32 char *
  33 simple_strncpy (char *dst, const char *src, size_t n)
  34 {
  35   char *ret = dst;
  36   while (n--)
  37     if ((*dst++ = *src++) == '\0')
  38       {
  39         while (n--)
  40           *dst++ = '\0';
  41         return ret;
  42       }
  43   return ret;
  44 }
  45
  46 char *
  47 stupid_strncpy (char *dst, const char *src, size_t n)
  48 {
  49   size_t nc = strnlen (src, n);
  50   size_t i;
  51
  52   for (i = 0; i < nc; ++i)
  53     dst[i] = src[i];
  54   for (; i < n; ++i)
  55     dst[i] = '\0';
  56   return dst;
  57 }
  58 #endif
  59
  60 typedef char *(*proto_t) (char *, const char *, size_t);
  61
  62 static void
  63 do_one_test (impl_t *impl, char *dst, const char *src, size_t len, size_t n)
  64 {
  65   if (CALL (impl, dst, src, n) != STRNCPY_RESULT (dst, len, n))
  66     {
  67       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  68              CALL (impl, dst, src, n), dst);
  69       ret = 1;
  70       return;
  71     }
  72
  73   if (memcmp (dst, src, len > n ? n : len) != 0)
  74     {
  75       error (0, 0, "Wrong result in function %s", impl->name);
  76       ret = 1;
  77       return;
  78     }
  79
  80   if (n > len)
  81     {
  82       size_t i;
  83
  84       for (i = len; i < n; ++i)
  85         if (dst [i] != '\0')
  86           {
  87             error (0, 0, "Wrong result in function %s", impl->name);
  88             ret = 1;
  89             return;
  90           }
  91     }
  92
  93   if (HP_TIMING_AVAIL)
  94     {
  95       hp_timing_t start __attribute__ ((unused));
  96       hp_timing_t stop __attribute__ ((unused));
  97       hp_timing_t best_time = ~ (hp_timing_t) 0;
  98       size_t i;
  99
 100       for (i = 0; i < 32; ++i)
 101         {
 102           HP_TIMING_NOW (start);
 103           CALL (impl, dst, src, n);
 104           HP_TIMING_NOW (stop);
 105           HP_TIMING_BEST (best_time, start, stop);
 106         }
 107
 108       printf ("\t%zd", (size_t) best_time);
 109     }
 110 }
 111
 112 static void
 113 do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char)
 114 {
 115   size_t i;
 116   char *s1, *s2;
 117
 118   align1 &= 7;
 119   if (align1 + len >= page_size)
 120     return;
 121
 122   align2 &= 7;
 123   if (align2 + len >= page_size)
 124     return;
 125
 126   s1 = (char *) (buf1 + align1);
 127   s2 = (char *) (buf2 + align2);
 128
 129   for (i = 0; i < len; ++i)
 130     s1[i] = 32 + 23 * i % (max_char - 32);
 131   s1[len] = 0;
 132   for (i = len + 1; i + align1 < page_size && i < len + 64; ++i)
 133     s1[i] = 32 + 32 * i % (max_char - 32);
 134
 135   if (HP_TIMING_AVAIL)
 136     printf ("Length %4zd, n %4zd, alignment %2zd/%2zd:", len, n, align1, align2);
 137
 138   FOR_EACH_IMPL (impl, 0)
 139     do_one_test (impl, s2, s1, len, n);
 140
 141   if (HP_TIMING_AVAIL)
 142     putchar ('\n');
 143 }
 144
 145 int
 146 test_main (void)
 147 {
 148   size_t i;
 149
 150   test_init ();
 151
 152   printf ("%28s", "");
 153   FOR_EACH_IMPL (impl, 0)
 154     printf ("\t%s", impl->name);
 155   putchar ('\n');
 156
 157   for (i = 1; i < 8; ++i)
 158     {
 159       do_test (i, i, 16, 16, 127);
 160       do_test (i, i, 16, 16, 255);
 161       do_test (i, 2 * i, 16, 16, 127);
 162       do_test (2 * i, i, 16, 16, 255);
 163       do_test (8 - i, 2 * i, 1 << i, 2 << i, 127);
 164       do_test (2 * i, 8 - i, 2 << i, 1 << i, 127);
 165       do_test (8 - i, 2 * i, 1 << i, 2 << i, 255);
 166       do_test (2 * i, 8 - i, 2 << i, 1 << i, 255);
 167     }
 168
 169   for (i = 1; i < 8; ++i)
 170     {
 171       do_test (0, 0, 4 << i, 8 << i, 127);
 172       do_test (0, 0, 16 << i, 8 << i, 127);
 173       do_test (8 - i, 2 * i, 4 << i, 8 << i, 127);
 174       do_test (8 - i, 2 * i, 16 << i, 8 << i, 127);
 175     }
 176
 177   return ret;
 178 }
 179
 180 #include "../test-skeleton.c"