benchtests/bench-strstr.c

   1 /* Measure strstr 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 #define TEST_MAIN
  20 #define TEST_NAME "strstr"
  21 #include "bench-string.h"
  22
  23
  24 #define STRSTR simple_strstr
  25 #include "../string/strstr.c"
  26
  27
  28 static char *
  29 stupid_strstr (const char *s1, const char *s2)
  30 {
  31   ssize_t s1len = strlen (s1);
  32   ssize_t s2len = strlen (s2);
  33
  34   if (s2len > s1len)
  35     return NULL;
  36
  37   for (ssize_t i = 0; i <= s1len - s2len; ++i)
  38     {
  39       size_t j;
  40       for (j = 0; j < s2len; ++j)
  41         if (s1[i + j] != s2[j])
  42           break;
  43       if (j == s2len)
  44         return (char *) s1 + i;
  45     }
  46
  47   return NULL;
  48 }
  49
  50
  51 typedef char *(*proto_t) (const char *, const char *);
  52
  53 IMPL (stupid_strstr, 0)
  54 IMPL (simple_strstr, 0)
  55 IMPL (strstr, 1)
  56
  57
  58 static void
  59 do_one_test (impl_t *impl, const char *s1, const char *s2, char *exp_result)
  60 {
  61   size_t i, iters = INNER_LOOP_ITERS;
  62   timing_t start, stop, cur;
  63
  64   TIMING_NOW (start);
  65   for (i = 0; i < iters; ++i)
  66     {
  67       CALL (impl, s1, s2);
  68     }
  69   TIMING_NOW (stop);
  70
  71   TIMING_DIFF (cur, start, stop);
  72
  73   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  74 }
  75
  76
  77 static void
  78 do_test (size_t align1, size_t align2, size_t len1, size_t len2,
  79          int fail)
  80 {
  81   char *s1 = (char *) (buf1 + align1);
  82   char *s2 = (char *) (buf2 + align2);
  83
  84   static const char d[] = "1234567890abcdef";
  85 #define dl (sizeof (d) - 1)
  86   char *ss2 = s2;
  87   for (size_t l = len2; l > 0; l = l > dl ? l - dl : 0)
  88     {
  89       size_t t = l > dl ? dl : l;
  90       ss2 = mempcpy (ss2, d, t);
  91     }
  92   s2[len2] = '\0';
  93
  94   if (fail)
  95     {
  96       char *ss1 = s1;
  97       for (size_t l = len1; l > 0; l = l > dl ? l - dl : 0)
  98         {
  99           size_t t = l > dl ? dl : l;
 100           memcpy (ss1, d, t);
 101           ++ss1[len2 > 7 ? 7 : len2 - 1];
 102           ss1 += t;
 103         }
 104     }
 105   else
 106     {
 107       memset (s1, '0', len1);
 108       memcpy (s1 + len1 - len2, s2, len2);
 109     }
 110   s1[len1] = '\0';
 111
 112   printf ("Length %4zd/%zd, alignment %2zd/%2zd, %s:",
 113           len1, len2, align1, align2, fail ? "fail" : "found");
 114
 115   FOR_EACH_IMPL (impl, 0)
 116     do_one_test (impl, s1, s2, fail ? NULL : s1 + len1 - len2);
 117
 118   putchar ('\n');
 119 }
 120
 121 static int
 122 test_main (void)
 123 {
 124   test_init ();
 125
 126   printf ("%23s", "");
 127   FOR_EACH_IMPL (impl, 0)
 128     printf ("\t%s", impl->name);
 129   putchar ('\n');
 130
 131   for (size_t klen = 2; klen < 32; ++klen)
 132     for (size_t hlen = 2 * klen; hlen < 16 * klen; hlen += klen)
 133       {
 134         do_test (0, 0, hlen, klen, 0);
 135         do_test (0, 0, hlen, klen, 1);
 136         do_test (0, 3, hlen, klen, 0);
 137         do_test (0, 3, hlen, klen, 1);
 138         do_test (0, 9, hlen, klen, 0);
 139         do_test (0, 9, hlen, klen, 1);
 140         do_test (0, 15, hlen, klen, 0);
 141         do_test (0, 15, hlen, klen, 1);
 142
 143         do_test (3, 0, hlen, klen, 0);
 144         do_test (3, 0, hlen, klen, 1);
 145         do_test (3, 3, hlen, klen, 0);
 146         do_test (3, 3, hlen, klen, 1);
 147         do_test (3, 9, hlen, klen, 0);
 148         do_test (3, 9, hlen, klen, 1);
 149         do_test (3, 15, hlen, klen, 0);
 150         do_test (3, 15, hlen, klen, 1);
 151
 152         do_test (9, 0, hlen, klen, 0);
 153         do_test (9, 0, hlen, klen, 1);
 154         do_test (9, 3, hlen, klen, 0);
 155         do_test (9, 3, hlen, klen, 1);
 156         do_test (9, 9, hlen, klen, 0);
 157         do_test (9, 9, hlen, klen, 1);
 158         do_test (9, 15, hlen, klen, 0);
 159         do_test (9, 15, hlen, klen, 1);
 160
 161         do_test (15, 0, hlen, klen, 0);
 162         do_test (15, 0, hlen, klen, 1);
 163         do_test (15, 3, hlen, klen, 0);
 164         do_test (15, 3, hlen, klen, 1);
 165         do_test (15, 9, hlen, klen, 0);
 166         do_test (15, 9, hlen, klen, 1);
 167         do_test (15, 15, hlen, klen, 0);
 168         do_test (15, 15, hlen, klen, 1);
 169       }
 170
 171   do_test (0, 0, page_size - 1, 16, 0);
 172   do_test (0, 0, page_size - 1, 16, 1);
 173
 174   return ret;
 175 }
 176
 177 #include <support/test-driver.c>