benchtests/bench-strncpy.c

   1 /* Measure strncpy functions.
   2    Copyright (C) 2013-2019 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 BIG_CHAR MAX_CHAR
  20
  21 #ifdef WIDE
  22 # define SMALL_CHAR 1273
  23 #else
  24 # define SMALL_CHAR 127
  25 #endif /* !WIDE */
  26
  27 #ifndef STRNCPY_RESULT
  28 # define STRNCPY_RESULT(dst, len, n) dst
  29 # define TEST_MAIN
  30 # ifndef WIDE
  31 #  define TEST_NAME "strncpy"
  32 # else
  33 #  define TEST_NAME "wcsncpy"
  34 # endif /* WIDE */
  35 # include "bench-string.h"
  36 # ifndef WIDE
  37 #  define SIMPLE_STRNCPY simple_strncpy
  38 #  define STUPID_STRNCPY stupid_strncpy
  39 # else
  40 #  define SIMPLE_STRNCPY simple_wcsncpy
  41 #  define STUPID_STRNCPY stupid_wcsncpy
  42 # endif /* WIDE */
  43
  44 CHAR *SIMPLE_STRNCPY (CHAR *, const CHAR *, size_t);
  45 CHAR *STUPID_STRNCPY (CHAR *, const CHAR *, size_t);
  46
  47 IMPL (STUPID_STRNCPY, 0)
  48 IMPL (SIMPLE_STRNCPY, 0)
  49 IMPL (STRNCPY, 1)
  50
  51 CHAR *
  52 SIMPLE_STRNCPY (CHAR *dst, const CHAR *src, size_t n)
  53 {
  54   CHAR *ret = dst;
  55   while (n--)
  56     if ((*dst++ = *src++) == '\0')
  57       {
  58         while (n--)
  59           *dst++ = '\0';
  60         return ret;
  61       }
  62   return ret;
  63 }
  64
  65 CHAR *
  66 STUPID_STRNCPY (CHAR *dst, const CHAR *src, size_t n)
  67 {
  68   size_t nc = STRNLEN (src, n);
  69   size_t i;
  70
  71   for (i = 0; i < nc; ++i)
  72     dst[i] = src[i];
  73   for (; i < n; ++i)
  74     dst[i] = '\0';
  75   return dst;
  76 }
  77 #endif /* !STRNCPY_RESULT */
  78
  79 typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
  80
  81 static void
  82 do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t len, size_t n)
  83 {
  84   size_t i, iters = INNER_LOOP_ITERS;
  85   timing_t start, stop, cur;
  86
  87   if (CALL (impl, dst, src, n) != STRNCPY_RESULT (dst, len, n))
  88     {
  89       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  90              CALL (impl, dst, src, n), dst);
  91       ret = 1;
  92       return;
  93     }
  94
  95   if (memcmp (dst, src, (len > n ? n : len) * sizeof (CHAR)) != 0)
  96     {
  97       error (0, 0, "Wrong result in function %s", impl->name);
  98       ret = 1;
  99       return;
 100     }
 101
 102   if (n > len)
 103     {
 104       size_t i;
 105
 106       for (i = len; i < n; ++i)
 107         if (dst [i] != '\0')
 108           {
 109             error (0, 0, "Wrong result in function %s", impl->name);
 110             ret = 1;
 111             return;
 112           }
 113     }
 114
 115   TIMING_NOW (start);
 116   for (i = 0; i < iters; ++i)
 117     {
 118       CALL (impl, dst, src, n);
 119     }
 120   TIMING_NOW (stop);
 121
 122   TIMING_DIFF (cur, start, stop);
 123
 124   TIMING_PRINT_MEAN ((double) cur, (double) iters);
 125 }
 126
 127 static void
 128 do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char)
 129 {
 130   size_t i;
 131   CHAR *s1, *s2;
 132
 133 /* For wcsncpy: align1 and align2 here mean alignment not in bytes,
 134    but in wchar_ts, in bytes it will equal to align * (sizeof (wchar_t)).  */
 135   align1 &= 7;
 136   if ((align1 + len) * sizeof (CHAR) >= page_size)
 137     return;
 138
 139   align2 &= 7;
 140   if ((align2 + len) * sizeof (CHAR) >= page_size)
 141     return;
 142
 143   s1 = (CHAR *) (buf1) + align1;
 144   s2 = (CHAR *) (buf2) + align2;
 145
 146   for (i = 0; i < len; ++i)
 147     s1[i] = 32 + 23 * i % (max_char - 32);
 148   s1[len] = 0;
 149   for (i = len + 1; (i + align1) * sizeof (CHAR) < page_size && i < len + 64;
 150        ++i)
 151     s1[i] = 32 + 32 * i % (max_char - 32);
 152
 153   printf ("Length %4zd, n %4zd, alignment %2zd/%2zd:", len, n, align1, align2);
 154
 155   FOR_EACH_IMPL (impl, 0)
 156     do_one_test (impl, s2, s1, len, n);
 157
 158   putchar ('\n');
 159 }
 160
 161 static int
 162 test_main (void)
 163 {
 164   size_t i;
 165
 166   test_init ();
 167
 168   printf ("%28s", "");
 169   FOR_EACH_IMPL (impl, 0)
 170     printf ("\t%s", impl->name);
 171   putchar ('\n');
 172
 173   for (i = 1; i < 8; ++i)
 174     {
 175       do_test (i, i, 16, 16, SMALL_CHAR);
 176       do_test (i, i, 16, 16, BIG_CHAR);
 177       do_test (i, 2 * i, 16, 16, SMALL_CHAR);
 178       do_test (2 * i, i, 16, 16, BIG_CHAR);
 179       do_test (8 - i, 2 * i, 1 << i, 2 << i, SMALL_CHAR);
 180       do_test (2 * i, 8 - i, 2 << i, 1 << i, SMALL_CHAR);
 181       do_test (8 - i, 2 * i, 1 << i, 2 << i, BIG_CHAR);
 182       do_test (2 * i, 8 - i, 2 << i, 1 << i, BIG_CHAR);
 183     }
 184
 185   for (i = 1; i < 8; ++i)
 186     {
 187       do_test (0, 0, 4 << i, 8 << i, SMALL_CHAR);
 188       do_test (0, 0, 16 << i, 8 << i, SMALL_CHAR);
 189       do_test (8 - i, 2 * i, 4 << i, 8 << i, SMALL_CHAR);
 190       do_test (8 - i, 2 * i, 16 << i, 8 << i, SMALL_CHAR);
 191     }
 192
 193   return ret;
 194 }
 195
 196 #include <support/test-driver.c>