benchtests/bench-memcmp.c

   1 /* Measure memcmp functions.
   2    Copyright (C) 2013-2018 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 #ifdef WIDE
  21 # define TEST_NAME "wmemcmp"
  22 #else
  23 # define TEST_NAME "memcmp"
  24 #endif
  25 #include "bench-string.h"
  26 #ifdef WIDE
  27 # include <inttypes.h>
  28 # include <wchar.h>
  29
  30 # define MEMCMP wmemcmp
  31 # define MEMCPY wmemcpy
  32 # define SIMPLE_MEMCMP simple_wmemcmp
  33 # define CHAR wchar_t
  34 # define UCHAR wchar_t
  35 # define CHARBYTES 4
  36 # define CHAR__MIN WCHAR_MIN
  37 # define CHAR__MAX WCHAR_MAX
  38 int
  39 simple_wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
  40 {
  41   int ret = 0;
  42   /* Warning!
  43         wmemcmp has to use SIGNED comparison for elements.
  44         memcmp has to use UNSIGNED comparison for elemnts.
  45   */
  46   while (n-- && (ret = *s1 < *s2 ? -1 : *s1 == *s2 ? 0 : 1) == 0) {s1++; s2++;}
  47   return ret;
  48 }
  49 #else
  50 # include <limits.h>
  51
  52 # define MEMCMP memcmp
  53 # define MEMCPY memcpy
  54 # define SIMPLE_MEMCMP simple_memcmp
  55 # define CHAR char
  56 # define MAX_CHAR 255
  57 # define UCHAR unsigned char
  58 # define CHARBYTES 1
  59 # define CHAR__MIN CHAR_MIN
  60 # define CHAR__MAX CHAR_MAX
  61
  62 int
  63 simple_memcmp (const char *s1, const char *s2, size_t n)
  64 {
  65   int ret = 0;
  66
  67   while (n-- && (ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) == 0);
  68   return ret;
  69 }
  70 #endif
  71
  72 # include "json-lib.h"
  73
  74 typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
  75
  76 IMPL (SIMPLE_MEMCMP, 0)
  77 IMPL (MEMCMP, 1)
  78
  79 static void
  80 do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s1,
  81              const CHAR *s2, size_t len, int exp_result)
  82 {
  83   size_t i, iters = INNER_LOOP_ITERS;
  84   timing_t start, stop, cur;
  85
  86   TIMING_NOW (start);
  87   for (i = 0; i < iters; ++i)
  88     {
  89       CALL (impl, s1, s2, len);
  90     }
  91   TIMING_NOW (stop);
  92
  93   TIMING_DIFF (cur, start, stop);
  94
  95   json_element_double (json_ctx, (double) cur / (double) iters);
  96 }
  97
  98 static void
  99 do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
 100          int exp_result)
 101 {
 102   size_t i;
 103   CHAR *s1, *s2;
 104
 105   if (len == 0)
 106     return;
 107
 108   align1 &= 63;
 109   if (align1 + (len + 1) * CHARBYTES >= page_size)
 110     return;
 111
 112   align2 &= 63;
 113   if (align2 + (len + 1) * CHARBYTES >= page_size)
 114     return;
 115
 116   json_element_object_begin (json_ctx);
 117   json_attr_uint (json_ctx, "length", (double) len);
 118   json_attr_uint (json_ctx, "align1", (double) align1);
 119   json_attr_uint (json_ctx, "align2", (double) align2);
 120   json_array_begin (json_ctx, "timings");
 121
 122   FOR_EACH_IMPL (impl, 0)
 123     {
 124       s1 = (CHAR *) (buf1 + align1);
 125       s2 = (CHAR *) (buf2 + align2);
 126
 127       for (i = 0; i < len; i++)
 128         s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % CHAR__MAX;
 129
 130       s1[len] = align1;
 131       s2[len] = align2;
 132       s2[len - 1] -= exp_result;
 133
 134       do_one_test (json_ctx, impl, s1, s2, len, exp_result);
 135       realloc_bufs ();
 136     }
 137
 138   json_array_end (json_ctx);
 139   json_element_object_end (json_ctx);
 140 }
 141
 142 int
 143 test_main (void)
 144 {
 145   json_ctx_t json_ctx;
 146   size_t i;
 147
 148   test_init ();
 149
 150   json_init (&json_ctx, 0, stdout);
 151
 152   json_document_begin (&json_ctx);
 153   json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
 154
 155   json_attr_object_begin (&json_ctx, "functions");
 156   json_attr_object_begin (&json_ctx, TEST_NAME);
 157   json_attr_string (&json_ctx, "bench-variant", "default");
 158
 159   json_array_begin (&json_ctx, "ifuncs");
 160   FOR_EACH_IMPL (impl, 0)
 161     json_element_string (&json_ctx, impl->name);
 162   json_array_end (&json_ctx);
 163
 164   json_array_begin (&json_ctx, "results");
 165   for (i = 1; i < 16; ++i)
 166     {
 167       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, 0);
 168       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, 1);
 169       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, -1);
 170     }
 171
 172   for (i = 0; i < 16; ++i)
 173     {
 174       do_test (&json_ctx, 0, 0, i, 0);
 175       do_test (&json_ctx, 0, 0, i, 1);
 176       do_test (&json_ctx, 0, 0, i, -1);
 177     }
 178
 179   for (i = 1; i < 10; ++i)
 180     {
 181       do_test (&json_ctx, 0, 0, 2 << i, 0);
 182       do_test (&json_ctx, 0, 0, 2 << i, 1);
 183       do_test (&json_ctx, 0, 0, 2 << i, -1);
 184       do_test (&json_ctx, 0, 0, 16 << i, 0);
 185       do_test (&json_ctx, (8 - i) * CHARBYTES, (2 * i) * CHARBYTES, 16 << i, 0);
 186       do_test (&json_ctx, 0, 0, 16 << i, 1);
 187       do_test (&json_ctx, 0, 0, 16 << i, -1);
 188     }
 189
 190   for (i = 1; i < 8; ++i)
 191     {
 192       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 0);
 193       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 1);
 194       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, -1);
 195     }
 196
 197   json_array_end (&json_ctx);
 198   json_attr_object_end (&json_ctx);
 199   json_attr_object_end (&json_ctx);
 200   json_document_end (&json_ctx);
 201
 202   return ret;
 203 }
 204
 205 #include <support/test-driver.c>