benchtests/bench-strncpy.c

   1 /* Measure strncpy functions.
   2    Copyright (C) 2013-2021 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    <https://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 #  define generic_strncpy generic_wcsncpy
  35 # endif /* WIDE */
  36 # include "bench-string.h"
  37
  38 CHAR *
  39 generic_strncpy (CHAR *dst, const CHAR *src, size_t n)
  40 {
  41   size_t nc = STRNLEN (src, n);
  42   if (nc != n)
  43     MEMSET (dst + nc, 0, n - nc);
  44   return MEMCPY (dst, src, nc);
  45 }
  46
  47 IMPL (STRNCPY, 1)
  48 IMPL (generic_strncpy, 0)
  49
  50 #endif /* !STRNCPY_RESULT */
  51
  52 typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
  53
  54 static void
  55 do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t len, size_t n)
  56 {
  57   size_t i, iters = INNER_LOOP_ITERS_LARGE * (4 / CHARBYTES);
  58   timing_t start, stop, cur;
  59
  60   if (CALL (impl, dst, src, n) != STRNCPY_RESULT (dst, len, n))
  61     {
  62       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  63              CALL (impl, dst, src, n), dst);
  64       ret = 1;
  65       return;
  66     }
  67
  68   if (memcmp (dst, src, (len > n ? n : len) * sizeof (CHAR)) != 0)
  69     {
  70       error (0, 0, "Wrong result in function %s", impl->name);
  71       ret = 1;
  72       return;
  73     }
  74
  75   if (n > len)
  76     {
  77       size_t i;
  78
  79       for (i = len; i < n; ++i)
  80         if (dst [i] != '\0')
  81           {
  82             error (0, 0, "Wrong result in function %s", impl->name);
  83             ret = 1;
  84             return;
  85           }
  86     }
  87
  88   TIMING_NOW (start);
  89   for (i = 0; i < iters; ++i)
  90     {
  91       CALL (impl, dst, src, n);
  92     }
  93   TIMING_NOW (stop);
  94
  95   TIMING_DIFF (cur, start, stop);
  96
  97   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  98 }
  99
 100 static void
 101 do_test (size_t align1, size_t align2, size_t len, size_t n, int max_char)
 102 {
 103   size_t i;
 104   CHAR *s1, *s2;
 105
 106 /* For wcsncpy: align1 and align2 here mean alignment not in bytes,
 107    but in wchar_ts, in bytes it will equal to align * (sizeof (wchar_t)).  */
 108   align1 &= 7;
 109   if ((align1 + len) * sizeof (CHAR) >= page_size)
 110     return;
 111
 112   align2 &= 7;
 113   if ((align2 + len) * sizeof (CHAR) >= page_size)
 114     return;
 115
 116   s1 = (CHAR *) (buf1) + align1;
 117   s2 = (CHAR *) (buf2) + align2;
 118
 119   for (i = 0; i < len; ++i)
 120     s1[i] = 32 + 23 * i % (max_char - 32);
 121   s1[len] = 0;
 122   for (i = len + 1; (i + align1) * sizeof (CHAR) < page_size && i < len + 64;
 123        ++i)
 124     s1[i] = 32 + 32 * i % (max_char - 32);
 125
 126   printf ("Length %4zd, n %4zd, alignment %2zd/%2zd:", len, n, align1, align2);
 127
 128   FOR_EACH_IMPL (impl, 0)
 129     do_one_test (impl, s2, s1, len, n);
 130
 131   putchar ('\n');
 132 }
 133
 134 static int
 135 test_main (void)
 136 {
 137   size_t i;
 138
 139   test_init ();
 140
 141   printf ("%28s", "");
 142   FOR_EACH_IMPL (impl, 0)
 143     printf ("\t%s", impl->name);
 144   putchar ('\n');
 145
 146   for (i = 1; i < 8; ++i)
 147     {
 148       do_test (i, i, 16, 16, SMALL_CHAR);
 149       do_test (i, i, 16, 16, BIG_CHAR);
 150       do_test (i, 2 * i, 16, 16, SMALL_CHAR);
 151       do_test (2 * i, i, 16, 16, BIG_CHAR);
 152       do_test (8 - i, 2 * i, 1 << i, 2 << i, SMALL_CHAR);
 153       do_test (2 * i, 8 - i, 2 << i, 1 << i, SMALL_CHAR);
 154       do_test (8 - i, 2 * i, 1 << i, 2 << i, BIG_CHAR);
 155       do_test (2 * i, 8 - i, 2 << i, 1 << i, BIG_CHAR);
 156     }
 157
 158   for (i = 1; i < 8; ++i)
 159     {
 160       do_test (0, 0, 4 << i, 8 << i, SMALL_CHAR);
 161       do_test (0, 0, 16 << i, 8 << i, SMALL_CHAR);
 162       do_test (8 - i, 2 * i, 4 << i, 8 << i, SMALL_CHAR);
 163       do_test (8 - i, 2 * i, 16 << i, 8 << i, SMALL_CHAR);
 164     }
 165
 166   return ret;
 167 }
 168
 169 #include <support/test-driver.c>