benchtests/bench-memchr.c

   1 /* Measure memchr 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 #define TEST_MAIN
  20 #define TEST_NAME "memchr"
  21 #include "bench-string.h"
  22
  23 typedef char *(*proto_t) (const char *, int, size_t);
  24 char *simple_memchr (const char *, int, size_t);
  25
  26 IMPL (simple_memchr, 0)
  27 IMPL (memchr, 1)
  28
  29 char *
  30 simple_memchr (const char *s, int c, size_t n)
  31 {
  32   while (n--)
  33     if (*s++ == (char) c)
  34       return (char *) s - 1;
  35   return NULL;
  36 }
  37
  38 static void
  39 do_one_test (impl_t *impl, const char *s, int c, size_t n, char *exp_res)
  40 {
  41   char *res = CALL (impl, s, c, n);
  42   if (res != exp_res)
  43     {
  44       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  45              res, exp_res);
  46       ret = 1;
  47       return;
  48     }
  49
  50   if (HP_TIMING_AVAIL)
  51     {
  52       hp_timing_t start __attribute ((unused));
  53       hp_timing_t stop __attribute ((unused));
  54       hp_timing_t best_time = ~ (hp_timing_t) 0;
  55       size_t i;
  56
  57       for (i = 0; i < 32; ++i)
  58         {
  59           HP_TIMING_NOW (start);
  60           CALL (impl, s, c, n);
  61           HP_TIMING_NOW (stop);
  62           HP_TIMING_BEST (best_time, start, stop);
  63         }
  64
  65       printf ("\t%zd", (size_t) best_time);
  66     }
  67 }
  68
  69 static void
  70 do_test (size_t align, size_t pos, size_t len, int seek_char)
  71 {
  72   size_t i;
  73   char *result;
  74
  75   align &= 7;
  76   if (align + len >= page_size)
  77     return;
  78
  79   for (i = 0; i < len; ++i)
  80     {
  81       buf1[align + i] = 1 + 23 * i % 127;
  82       if (buf1[align + i] == seek_char)
  83         buf1[align + i] = seek_char + 1;
  84     }
  85   buf1[align + len] = 0;
  86
  87   if (pos < len)
  88     {
  89       buf1[align + pos] = seek_char;
  90       buf1[align + len] = -seek_char;
  91       result = (char *) (buf1 + align + pos);
  92     }
  93   else
  94     {
  95       result = NULL;
  96       buf1[align + len] = seek_char;
  97     }
  98
  99   if (HP_TIMING_AVAIL)
 100     printf ("Length %4zd, alignment %2zd:", pos, align);
 101
 102   FOR_EACH_IMPL (impl, 0)
 103     do_one_test (impl, (char *) (buf1 + align), seek_char, len, result);
 104
 105   if (HP_TIMING_AVAIL)
 106     putchar ('\n');
 107 }
 108
 109 int
 110 test_main (void)
 111 {
 112   size_t i;
 113
 114   test_init ();
 115
 116   printf ("%20s", "");
 117   FOR_EACH_IMPL (impl, 0)
 118     printf ("\t%s", impl->name);
 119   putchar ('\n');
 120
 121   for (i = 1; i < 8; ++i)
 122     {
 123       do_test (0, 16 << i, 2048, 23);
 124       do_test (i, 64, 256, 23);
 125       do_test (0, 16 << i, 2048, 0);
 126       do_test (i, 64, 256, 0);
 127     }
 128   for (i = 1; i < 32; ++i)
 129     {
 130       do_test (0, i, i + 1, 23);
 131       do_test (0, i, i + 1, 0);
 132     }
 133
 134   return ret;
 135 }
 136
 137 #include "../test-skeleton.c"