benchtests/bench-rawmemchr.c

   1 /* Measure memchr functions.
   2    Copyright (C) 2013-2017 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 #include <assert.h>
  20
  21 #define TEST_MAIN
  22 #define TEST_NAME "rawmemchr"
  23 #include "bench-string.h"
  24
  25 typedef char *(*proto_t) (const char *, int);
  26 char *simple_rawmemchr (const char *, int);
  27
  28 IMPL (simple_rawmemchr, 0)
  29 IMPL (rawmemchr, 1)
  30
  31 char *
  32 simple_rawmemchr (const char *s, int c)
  33 {
  34   while (1)
  35     if (*s++ == (char) c)
  36       return (char *) s - 1;
  37   return NULL;
  38 }
  39
  40 static void
  41 do_one_test (impl_t *impl, const char *s, int c, char *exp_res)
  42 {
  43   size_t i, iters = INNER_LOOP_ITERS;
  44   timing_t start, stop, cur;
  45   char *res = CALL (impl, s, c);
  46   if (res != exp_res)
  47     {
  48       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  49              res, exp_res);
  50       ret = 1;
  51       return;
  52     }
  53
  54   TIMING_NOW (start);
  55   for (i = 0; i < iters; ++i)
  56     {
  57       CALL (impl, s, c);
  58     }
  59   TIMING_NOW (stop);
  60
  61   TIMING_DIFF (cur, start, stop);
  62
  63   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  64 }
  65
  66 static void
  67 do_test (size_t align, size_t pos, size_t len, int seek_char)
  68 {
  69   size_t i;
  70   char *result;
  71
  72   align &= 7;
  73   if (align + len >= page_size)
  74     return;
  75
  76   for (i = 0; i < len; ++i)
  77     {
  78       buf1[align + i] = 1 + 23 * i % 127;
  79       if (buf1[align + i] == seek_char)
  80         buf1[align + i] = seek_char + 1;
  81     }
  82   buf1[align + len] = 0;
  83
  84   assert (pos < len);
  85
  86   buf1[align + pos] = seek_char;
  87   buf1[align + len] = -seek_char;
  88   result = (char *) (buf1 + align + pos);
  89
  90   printf ("Length %4zd, alignment %2zd:", pos, align);
  91
  92   FOR_EACH_IMPL (impl, 0)
  93     do_one_test (impl, (char *) (buf1 + align), seek_char, result);
  94
  95   putchar ('\n');
  96 }
  97
  98 int
  99 test_main (void)
 100 {
 101   size_t i;
 102
 103   test_init ();
 104
 105   printf ("%20s", "");
 106   FOR_EACH_IMPL (impl, 0)
 107     printf ("\t%s", impl->name);
 108   putchar ('\n');
 109
 110   for (i = 1; i < 7; ++i)
 111     {
 112       do_test (0, 16 << i, 2048, 23);
 113       do_test (i, 64, 256, 23);
 114       do_test (0, 16 << i, 2048, 0);
 115       do_test (i, 64, 256, 0);
 116     }
 117   for (i = 1; i < 32; ++i)
 118     {
 119       do_test (0, i, i + 1, 23);
 120       do_test (0, i, i + 1, 0);
 121     }
 122
 123   return ret;
 124 }
 125
 126 #include <support/test-driver.c>