benchtests/bench-strlen.c

   1 /* Measure STRLEN 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 #ifndef WIDE
  21 # define TEST_NAME "strlen"
  22 #else
  23 # define TEST_NAME "wcslen"
  24 #endif
  25 #include "bench-string.h"
  26
  27 #ifndef WIDE
  28 # define STRLEN strlen
  29 # define CHAR char
  30 # define MAX_CHAR CHAR_MAX
  31 #else
  32 # include <wchar.h>
  33 # define STRLEN wcslen
  34 # define CHAR wchar_t
  35 # define MAX_CHAR WCHAR_MAX
  36 #endif
  37
  38 typedef size_t (*proto_t) (const CHAR *);
  39
  40 size_t
  41 simple_STRLEN (const CHAR *s)
  42 {
  43   const CHAR *p;
  44
  45   for (p = s; *p; ++p);
  46   return p - s;
  47 }
  48
  49 #ifndef WIDE
  50 size_t
  51 builtin_strlen (const CHAR *p)
  52 {
  53   return __builtin_strlen (p);
  54 }
  55 IMPL (builtin_strlen, 0)
  56 #endif
  57
  58 IMPL (simple_STRLEN, 0)
  59 IMPL (STRLEN, 1)
  60
  61
  62 static void
  63 do_one_test (impl_t *impl, const CHAR *s, size_t exp_len)
  64 {
  65   size_t len = CALL (impl, s), i, iters = INNER_LOOP_ITERS;
  66   timing_t start, stop, cur;
  67
  68   if (len != exp_len)
  69     {
  70       error (0, 0, "Wrong result in function %s %zd %zd", impl->name,
  71              len, exp_len);
  72       ret = 1;
  73       return;
  74     }
  75
  76   TIMING_NOW (start);
  77   for (i = 0; i < iters; ++i)
  78     {
  79       CALL (impl, s);
  80     }
  81   TIMING_NOW (stop);
  82
  83   TIMING_DIFF (cur, start, stop);
  84
  85   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  86 }
  87
  88 static void
  89 do_test (size_t align, size_t len)
  90 {
  91   size_t i;
  92
  93   align &= 63;
  94   if (align + sizeof(CHAR) * len >= page_size)
  95     return;
  96
  97   CHAR *buf = (CHAR *) (buf1);
  98
  99   for (i = 0; i < len; ++i)
 100     buf[align + i] = 1 + 11111 * i % MAX_CHAR;
 101   buf[align + len] = 0;
 102
 103   printf ("Length %4zd, alignment %2zd:", len, align);
 104
 105   FOR_EACH_IMPL (impl, 0)
 106     do_one_test (impl, (CHAR *) (buf + align), len);
 107
 108   putchar ('\n');
 109 }
 110
 111 int
 112 test_main (void)
 113 {
 114   size_t i;
 115
 116   test_init ();
 117
 118   printf ("%20s", "");
 119   FOR_EACH_IMPL (impl, 0)
 120     printf ("\t%s", impl->name);
 121   putchar ('\n');
 122
 123   /* Checking with only 4 * N alignments for wcslen, other alignments are wrong for wchar_t type arrays*/
 124
 125   for (i = 1; i < 8; ++i)
 126   {
 127     do_test (sizeof(CHAR) * i, i);
 128     do_test (0, i);
 129   }
 130
 131   for (i = 2; i <= 12; ++i)
 132     {
 133       do_test (0, 1 << i);
 134       do_test (sizeof(CHAR) * 7, 1 << i);
 135       do_test (sizeof(CHAR) * i, 1 << i);
 136       do_test (sizeof(CHAR) * i, (size_t)((1 << i) / 1.5));
 137     }
 138
 139   return ret;
 140 }
 141
 142 #include <support/test-driver.c>