benchtests/bench-memccpy.c

   1 /* Measure memccpy 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 "memccpy"
  21 #include "bench-string.h"
  22
  23 void *simple_memccpy (void *, const void *, int, size_t);
  24 void *stupid_memccpy (void *, const void *, int, size_t);
  25
  26 IMPL (stupid_memccpy, 0)
  27 IMPL (simple_memccpy, 0)
  28 IMPL (memccpy, 1)
  29
  30 void *
  31 simple_memccpy (void *dst, const void *src, int c, size_t n)
  32 {
  33   const char *s = src;
  34   char *d = dst;
  35
  36   while (n-- > 0)
  37     if ((*d++ = *s++) == (char) c)
  38       return d;
  39
  40   return NULL;
  41 }
  42
  43 void *
  44 stupid_memccpy (void *dst, const void *src, int c, size_t n)
  45 {
  46   void *p = memchr (src, c, n);
  47
  48   if (p != NULL)
  49     return mempcpy (dst, src, p - src + 1);
  50
  51   memcpy (dst, src, n);
  52   return NULL;
  53 }
  54
  55 typedef void *(*proto_t) (void *, const void *, int c, size_t);
  56
  57 static void
  58 do_one_test (impl_t *impl, void *dst, const void *src, int c, size_t len,
  59              size_t n)
  60 {
  61   void *expect = len > n ? NULL : (char *) dst + len;
  62   if (CALL (impl, dst, src, c, n) != expect)
  63     {
  64       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  65              CALL (impl, dst, src, c, n), expect);
  66       ret = 1;
  67       return;
  68     }
  69
  70   if (memcmp (dst, src, len > n ? n : len) != 0)
  71     {
  72       error (0, 0, "Wrong result in function %s", impl->name);
  73       ret = 1;
  74       return;
  75     }
  76
  77   if (HP_TIMING_AVAIL)
  78     {
  79       hp_timing_t start __attribute__ ((unused));
  80       hp_timing_t stop __attribute__ ((unused));
  81       hp_timing_t best_time = ~ (hp_timing_t) 0;
  82       size_t i;
  83
  84       for (i = 0; i < 32; ++i)
  85         {
  86           HP_TIMING_NOW (start);
  87           CALL (impl, dst, src, c, n);
  88           HP_TIMING_NOW (stop);
  89           HP_TIMING_BEST (best_time, start, stop);
  90         }
  91
  92       printf ("\t%zd", (size_t) best_time);
  93     }
  94 }
  95
  96 static void
  97 do_test (size_t align1, size_t align2, int c, size_t len, size_t n,
  98          int max_char)
  99 {
 100   size_t i;
 101   char *s1, *s2;
 102
 103   align1 &= 7;
 104   if (align1 + len >= page_size)
 105     return;
 106
 107   align2 &= 7;
 108   if (align2 + len >= page_size)
 109     return;
 110
 111   s1 = (char *) (buf1 + align1);
 112   s2 = (char *) (buf2 + align2);
 113
 114   for (i = 0; i < len - 1; ++i)
 115     {
 116       s1[i] = 32 + 23 * i % (max_char - 32);
 117       if (s1[i] == (char) c)
 118         --s1[i];
 119     }
 120   s1[len - 1] = c;
 121   for (i = len; i + align1 < page_size && i < len + 64; ++i)
 122     s1[i] = 32 + 32 * i % (max_char - 32);
 123
 124   if (HP_TIMING_AVAIL)
 125     printf ("Length %4zd, n %4zd, char %d, alignment %2zd/%2zd:", len, n, c, align1, align2);
 126
 127   FOR_EACH_IMPL (impl, 0)
 128     do_one_test (impl, s2, s1, c, len, n);
 129
 130   if (HP_TIMING_AVAIL)
 131     putchar ('\n');
 132 }
 133
 134 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, 12, 16, 16, 127);
 149       do_test (i, i, 23, 16, 16, 255);
 150       do_test (i, 2 * i, 28, 16, 16, 127);
 151       do_test (2 * i, i, 31, 16, 16, 255);
 152       do_test (8 - i, 2 * i, 1, 1 << i, 2 << i, 127);
 153       do_test (2 * i, 8 - i, 17, 2 << i, 1 << i, 127);
 154       do_test (8 - i, 2 * i, 0, 1 << i, 2 << i, 255);
 155       do_test (2 * i, 8 - i, i, 2 << i, 1 << i, 255);
 156     }
 157
 158   for (i = 1; i < 8; ++i)
 159     {
 160       do_test (0, 0, i, 4 << i, 8 << i, 127);
 161       do_test (0, 0, i, 16 << i, 8 << i, 127);
 162       do_test (8 - i, 2 * i, i, 4 << i, 8 << i, 127);
 163       do_test (8 - i, 2 * i, i, 16 << i, 8 << i, 127);
 164     }
 165
 166   return ret;
 167 }
 168
 169 #include "../test-skeleton.c"