benchtests/bench-memchr.c

   1 /* Measure memchr 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef WIDE
  20 # define SMALL_CHAR 127
  21 #else
  22 # define SMALL_CHAR 1273
  23 #endif /* WIDE */
  24
  25 #ifndef USE_AS_MEMRCHR
  26 # define TEST_MAIN
  27 # ifndef WIDE
  28 #  define TEST_NAME "memchr"
  29 # else
  30 #  define TEST_NAME "wmemchr"
  31 # endif /* WIDE */
  32 # include "bench-string.h"
  33
  34 # ifndef WIDE
  35 #  define SIMPLE_MEMCHR simple_memchr
  36 # else
  37 #  define SIMPLE_MEMCHR simple_wmemchr
  38 # endif /* WIDE */
  39
  40 typedef CHAR *(*proto_t) (const CHAR *, int, size_t);
  41 CHAR *SIMPLE_MEMCHR (const CHAR *, int, size_t);
  42
  43 IMPL (SIMPLE_MEMCHR, 0)
  44 IMPL (MEMCHR, 1)
  45
  46 CHAR *
  47 SIMPLE_MEMCHR (const CHAR *s, int c, size_t n)
  48 {
  49   while (n--)
  50     if (*s++ == (CHAR) c)
  51       return (CHAR *) s - 1;
  52   return NULL;
  53 }
  54 #endif /* !USE_AS_MEMRCHR */
  55
  56 static void
  57 do_one_test (impl_t *impl, const CHAR *s, int c, size_t n)
  58 {
  59   size_t i, iters = INNER_LOOP_ITERS_LARGE;
  60   timing_t start, stop, cur;
  61
  62   TIMING_NOW (start);
  63   for (i = 0; i < iters; ++i)
  64     {
  65       CALL (impl, s, c, n);
  66     }
  67   TIMING_NOW (stop);
  68
  69   TIMING_DIFF (cur, start, stop);
  70
  71   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  72 }
  73
  74 static void
  75 do_test (size_t align, size_t pos, size_t len, int seek_char)
  76 {
  77   size_t i;
  78
  79   align &= 7;
  80   if ((align + len) * sizeof (CHAR) >= page_size)
  81     return;
  82
  83   CHAR *buf = (CHAR *) (buf1);
  84
  85   for (i = 0; i < len; ++i)
  86     {
  87       buf[align + i] = 1 + 23 * i % SMALL_CHAR;
  88       if (buf[align + i] == seek_char)
  89         buf[align + i] = seek_char + 1;
  90     }
  91   buf[align + len] = 0;
  92
  93   if (pos < len)
  94     {
  95       buf[align + pos] = seek_char;
  96       buf[align + len] = -seek_char;
  97     }
  98   else
  99     {
 100       buf[align + len] = seek_char;
 101     }
 102
 103   printf ("Length %4zd, position %4zd, alignment %2zd:",
 104           len, pos, align);
 105
 106   FOR_EACH_IMPL (impl, 0)
 107     do_one_test (impl, (CHAR *) (buf + align), seek_char, len);
 108
 109   putchar ('\n');
 110 }
 111
 112 int
 113 test_main (void)
 114 {
 115   size_t i;
 116
 117   test_init ();
 118
 119   printf ("%20s", "");
 120   FOR_EACH_IMPL (impl, 0)
 121     printf ("\t%s", impl->name);
 122   putchar ('\n');
 123
 124   for (i = 1; i < 8; ++i)
 125     {
 126       do_test (0, 16 << i, 2048, 23);
 127       do_test (i, 64, 256, 23);
 128       do_test (0, 16 << i, 2048, 0);
 129       do_test (i, 64, 256, 0);
 130 #ifdef USE_AS_MEMRCHR
 131       /* Also test the position close to the beginning for memrchr.  */
 132       do_test (0, i, 256, 23);
 133       do_test (0, i, 256, 0);
 134       do_test (i, i, 256, 23);
 135       do_test (i, i, 256, 0);
 136 #endif
 137     }
 138   for (i = 1; i < 32; ++i)
 139     {
 140       do_test (0, i, i + 1, 23);
 141       do_test (0, i, i + 1, 0);
 142       do_test (i, i, i + 1, 23);
 143       do_test (i, i, i + 1, 0);
 144 #ifdef USE_AS_MEMRCHR
 145       /* Also test the position close to the beginning for memrchr.  */
 146       do_test (0, 1, i + 1, 23);
 147       do_test (0, 2, i + 1, 0);
 148 #endif
 149     }
 150
 151   return ret;
 152 }
 153
 154 #include <support/test-driver.c>