benchtests/bench-memchr.c

   1 /* Measure memchr functions.
   2    Copyright (C) 2013-2018 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 WIDE
  20 # define CHAR char
  21 # define SMALL_CHAR 127
  22 #else
  23 # include <wchar.h>
  24 # define CHAR wchar_t
  25 # define SMALL_CHAR 1273
  26 #endif /* WIDE */
  27
  28 #ifndef USE_AS_MEMRCHR
  29 # define TEST_MAIN
  30 # ifndef WIDE
  31 #  define TEST_NAME "memchr"
  32 # else
  33 #  define TEST_NAME "wmemchr"
  34 # endif /* WIDE */
  35 # include "bench-string.h"
  36
  37 # ifndef WIDE
  38 #  define MEMCHR memchr
  39 #  define SIMPLE_MEMCHR simple_memchr
  40 # else
  41 #  define MEMCHR wmemchr
  42 #  define SIMPLE_MEMCHR simple_wmemchr
  43 # endif /* WIDE */
  44
  45 typedef CHAR *(*proto_t) (const CHAR *, int, size_t);
  46 CHAR *SIMPLE_MEMCHR (const CHAR *, int, size_t);
  47
  48 IMPL (SIMPLE_MEMCHR, 0)
  49 IMPL (MEMCHR, 1)
  50
  51 CHAR *
  52 SIMPLE_MEMCHR (const CHAR *s, int c, size_t n)
  53 {
  54   while (n--)
  55     if (*s++ == (CHAR) c)
  56       return (CHAR *) s - 1;
  57   return NULL;
  58 }
  59 #endif /* !USE_AS_MEMRCHR */
  60
  61 static void
  62 do_one_test (impl_t *impl, const CHAR *s, int c, size_t n)
  63 {
  64   size_t i, iters = INNER_LOOP_ITERS;
  65   timing_t start, stop, cur;
  66
  67   TIMING_NOW (start);
  68   for (i = 0; i < iters; ++i)
  69     {
  70       CALL (impl, s, c, n);
  71     }
  72   TIMING_NOW (stop);
  73
  74   TIMING_DIFF (cur, start, stop);
  75
  76   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  77 }
  78
  79 static void
  80 do_test (size_t align, size_t pos, size_t len, int seek_char)
  81 {
  82   size_t i;
  83
  84   align &= 7;
  85   if ((align + len) * sizeof (CHAR) >= page_size)
  86     return;
  87
  88   CHAR *buf = (CHAR *) (buf1);
  89
  90   for (i = 0; i < len; ++i)
  91     {
  92       buf[align + i] = 1 + 23 * i % SMALL_CHAR;
  93       if (buf[align + i] == seek_char)
  94         buf[align + i] = seek_char + 1;
  95     }
  96   buf[align + len] = 0;
  97
  98   if (pos < len)
  99     {
 100       buf[align + pos] = seek_char;
 101       buf[align + len] = -seek_char;
 102     }
 103   else
 104     {
 105       buf[align + len] = seek_char;
 106     }
 107
 108   printf ("Length %4zd, position %4zd, alignment %2zd:",
 109           len, pos, align);
 110
 111   FOR_EACH_IMPL (impl, 0)
 112     do_one_test (impl, (CHAR *) (buf + align), seek_char, len);
 113
 114   putchar ('\n');
 115 }
 116
 117 int
 118 test_main (void)
 119 {
 120   size_t i;
 121
 122   test_init ();
 123
 124   printf ("%20s", "");
 125   FOR_EACH_IMPL (impl, 0)
 126     printf ("\t%s", impl->name);
 127   putchar ('\n');
 128
 129   for (i = 1; i < 8; ++i)
 130     {
 131       do_test (0, 16 << i, 2048, 23);
 132       do_test (i, 64, 256, 23);
 133       do_test (0, 16 << i, 2048, 0);
 134       do_test (i, 64, 256, 0);
 135 #ifdef USE_AS_MEMRCHR
 136       /* Also test the position close to the beginning for memrchr.  */
 137       do_test (0, i, 256, 23);
 138       do_test (0, i, 256, 0);
 139       do_test (i, i, 256, 23);
 140       do_test (i, i, 256, 0);
 141 #endif
 142     }
 143   for (i = 1; i < 32; ++i)
 144     {
 145       do_test (0, i, i + 1, 23);
 146       do_test (0, i, i + 1, 0);
 147       do_test (i, i, i + 1, 23);
 148       do_test (i, i, i + 1, 0);
 149 #ifdef USE_AS_MEMRCHR
 150       /* Also test the position close to the beginning for memrchr.  */
 151       do_test (0, 1, i + 1, 23);
 152       do_test (0, 2, i + 1, 0);
 153 #endif
 154     }
 155
 156   return ret;
 157 }
 158
 159 #include <support/test-driver.c>