benchtests/bench-rawmemchr.c

   1 /* Measure memchr functions.
   2    Copyright (C) 2013-2021 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <assert.h>
  20 #include <stdint.h>
  21
  22 #define TEST_MAIN
  23 #define TEST_NAME "rawmemchr"
  24 #include "bench-string.h"
  25
  26 typedef char *(*proto_t) (const char *, int);
  27
  28 char *
  29 generic_rawmemchr (const char *s, int c)
  30 {
  31   if (c != 0)
  32     return memchr (s, c, PTRDIFF_MAX);
  33   return (char *)s + strlen (s);
  34 }
  35
  36 IMPL (rawmemchr, 1)
  37 IMPL (generic_rawmemchr, 0)
  38
  39 static void
  40 do_one_test (impl_t *impl, const char *s, int c, char *exp_res)
  41 {
  42   size_t i, iters = INNER_LOOP_ITERS_LARGE * 4;
  43   timing_t start, stop, cur;
  44   char *res = CALL (impl, s, c);
  45   if (res != exp_res)
  46     {
  47       error (0, 0, "Wrong result in function %s %p %p", impl->name,
  48              res, exp_res);
  49       ret = 1;
  50       return;
  51     }
  52
  53   TIMING_NOW (start);
  54   for (i = 0; i < iters; ++i)
  55     {
  56       CALL (impl, s, c);
  57     }
  58   TIMING_NOW (stop);
  59
  60   TIMING_DIFF (cur, start, stop);
  61
  62   TIMING_PRINT_MEAN ((double) cur, (double) iters);
  63 }
  64
  65 static void
  66 do_test (size_t align, size_t pos, size_t len, int seek_char)
  67 {
  68   size_t i;
  69   char *result;
  70
  71   align &= 7;
  72   if (align + len >= page_size)
  73     return;
  74
  75   for (i = 0; i < len; ++i)
  76     {
  77       buf1[align + i] = 1 + 23 * i % 127;
  78       if (buf1[align + i] == seek_char)
  79         buf1[align + i] = seek_char + 1;
  80     }
  81   buf1[align + len] = 0;
  82
  83   assert (pos < len);
  84
  85   buf1[align + pos] = seek_char;
  86   buf1[align + len] = -seek_char;
  87   result = (char *) (buf1 + align + pos);
  88
  89   printf ("Length %4zd, alignment %2zd:", pos, align);
  90
  91   FOR_EACH_IMPL (impl, 0)
  92     do_one_test (impl, (char *) (buf1 + align), seek_char, result);
  93
  94   putchar ('\n');
  95 }
  96
  97 int
  98 test_main (void)
  99 {
 100   size_t i;
 101
 102   test_init ();
 103
 104   printf ("%20s", "");
 105   FOR_EACH_IMPL (impl, 0)
 106     printf ("\t%s", impl->name);
 107   putchar ('\n');
 108
 109   for (i = 1; i < 7; ++i)
 110     {
 111       do_test (0, 16 << i, 2048, 23);
 112       do_test (i, 64, 256, 23);
 113       do_test (0, 16 << i, 2048, 0);
 114       do_test (i, 64, 256, 0);
 115     }
 116   for (i = 1; i < 32; ++i)
 117     {
 118       do_test (0, i, i + 1, 23);
 119       do_test (0, i, i + 1, 0);
 120     }
 121
 122   return ret;
 123 }
 124
 125 #include <support/test-driver.c>