benchtests/bench-memcpy.c

   1 /* Measure memcpy functions.
   2    Copyright (C) 2013-2016 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 MEMCPY_RESULT
  20 # define MEMCPY_RESULT(dst, len) dst
  21 # define MIN_PAGE_SIZE 131072
  22 # define TEST_MAIN
  23 # define TEST_NAME "memcpy"
  24 # include "bench-string.h"
  25
  26 char *simple_memcpy (char *, const char *, size_t);
  27 char *builtin_memcpy (char *, const char *, size_t);
  28
  29 IMPL (simple_memcpy, 0)
  30 IMPL (builtin_memcpy, 0)
  31 IMPL (memcpy, 1)
  32
  33 char *
  34 simple_memcpy (char *dst, const char *src, size_t n)
  35 {
  36   char *ret = dst;
  37   while (n--)
  38     *dst++ = *src++;
  39   return ret;
  40 }
  41
  42 char *
  43 builtin_memcpy (char *dst, const char *src, size_t n)
  44 {
  45   return __builtin_memcpy (dst, src, n);
  46 }
  47 #endif
  48
  49 typedef char *(*proto_t) (char *, const char *, size_t);
  50
  51 static void
  52 do_one_test (impl_t *impl, char *dst, const char *src,
  53              size_t len)
  54 {
  55   size_t i, iters = INNER_LOOP_ITERS;
  56   timing_t start, stop, cur;
  57
  58   if (CALL (impl, dst, src, len) != MEMCPY_RESULT (dst, len))
  59     {
  60       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  61              CALL (impl, dst, src, len), MEMCPY_RESULT (dst, len));
  62       ret = 1;
  63       return;
  64     }
  65
  66   if (memcmp (dst, src, len) != 0)
  67     {
  68       error (0, 0, "Wrong result in function %s dst \"%s\" src \"%s\"",
  69              impl->name, dst, src);
  70       ret = 1;
  71       return;
  72     }
  73
  74   TIMING_NOW (start);
  75   for (i = 0; i < iters; ++i)
  76     {
  77       CALL (impl, dst, src, len);
  78     }
  79   TIMING_NOW (stop);
  80
  81   TIMING_DIFF (cur, start, stop);
  82
  83   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  84 }
  85
  86 static void
  87 do_test (size_t align1, size_t align2, size_t len)
  88 {
  89   size_t i, j;
  90   char *s1, *s2;
  91
  92   align1 &= 63;
  93   if (align1 + len >= page_size)
  94     return;
  95
  96   align2 &= 63;
  97   if (align2 + len >= page_size)
  98     return;
  99
 100   s1 = (char *) (buf1 + align1);
 101   s2 = (char *) (buf2 + align2);
 102
 103   for (i = 0, j = 1; i < len; i++, j += 23)
 104     s1[i] = j;
 105
 106   printf ("Length %4zd, alignment %2zd/%2zd:", len, align1, align2);
 107
 108   FOR_EACH_IMPL (impl, 0)
 109     do_one_test (impl, s2, s1, len);
 110
 111   putchar ('\n');
 112 }
 113
 114 int
 115 test_main (void)
 116 {
 117   size_t i;
 118
 119   test_init ();
 120
 121   printf ("%23s", "");
 122   FOR_EACH_IMPL (impl, 0)
 123     printf ("\t%s", impl->name);
 124   putchar ('\n');
 125
 126   for (i = 0; i < 18; ++i)
 127     {
 128       do_test (0, 0, 1 << i);
 129       do_test (i, 0, 1 << i);
 130       do_test (0, i, 1 << i);
 131       do_test (i, i, 1 << i);
 132     }
 133
 134   for (i = 0; i < 32; ++i)
 135     {
 136       do_test (0, 0, i);
 137       do_test (i, 0, i);
 138       do_test (0, i, i);
 139       do_test (i, i, i);
 140     }
 141
 142   for (i = 3; i < 32; ++i)
 143     {
 144       if ((i & (i - 1)) == 0)
 145         continue;
 146       do_test (0, 0, 16 * i);
 147       do_test (i, 0, 16 * i);
 148       do_test (0, i, 16 * i);
 149       do_test (i, i, 16 * i);
 150     }
 151
 152   do_test (0, 0, getpagesize ());
 153
 154   return ret;
 155 }
 156
 157 #include "../test-skeleton.c"