benchtests/bench-memcmp.c

   1 /* Measure memcmp functions.
   2    Copyright (C) 2013-2023 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 #define TEST_MAIN
  20 #ifdef TEST_MEMCMPEQ
  21 # define TEST_NAME "__memcmpeq"
  22 # define SIMPLE_MEMCMP simple_memcmpeq
  23 #elif defined WIDE
  24 # define TEST_NAME "wmemcmp"
  25 # define SIMPLE_MEMCMP simple_wmemcmp
  26 #else
  27 # define TEST_NAME "memcmp"
  28 # define SIMPLE_MEMCMP simple_memcmp
  29 #endif
  30 #include "bench-string.h"
  31 #ifdef WIDE
  32
  33 int
  34 SIMPLE_MEMCMP (const wchar_t *s1, const wchar_t *s2, size_t n)
  35 {
  36   int ret = 0;
  37   /* Warning!
  38         wmemcmp has to use SIGNED comparison for elements.
  39         memcmp has to use UNSIGNED comparison for elemnts.
  40   */
  41   while (n-- && (ret = *s1 < *s2 ? -1 : *s1 == *s2 ? 0 : 1) == 0) {s1++; s2++;}
  42   return ret;
  43 }
  44 #else
  45 # include <limits.h>
  46
  47 int
  48 SIMPLE_MEMCMP (const char *s1, const char *s2, size_t n)
  49 {
  50   int ret = 0;
  51
  52   while (n-- && (ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) == 0);
  53   return ret;
  54 }
  55 #endif
  56
  57 # include "json-lib.h"
  58
  59 typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
  60
  61 IMPL (SIMPLE_MEMCMP, 0)
  62 IMPL (MEMCMP, 1)
  63
  64 static void
  65 do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s1,
  66              const CHAR *s2, size_t len)
  67 {
  68   size_t i, iters = INNER_LOOP_ITERS_LARGE;
  69   timing_t start, stop, cur;
  70
  71   TIMING_NOW (start);
  72   for (i = 0; i < iters; ++i)
  73     {
  74       CALL (impl, s1, s2, len);
  75     }
  76   TIMING_NOW (stop);
  77
  78   TIMING_DIFF (cur, start, stop);
  79
  80   json_element_double (json_ctx, (double) cur / (double) iters);
  81 }
  82
  83 static void
  84 do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
  85          int exp_result)
  86 {
  87   size_t i;
  88   CHAR *s1, *s2;
  89
  90   align1 &= (4096 - CHARBYTES);
  91   if (align1 + (len + 1) * CHARBYTES >= page_size)
  92     return;
  93
  94   align2 &= (4096 - CHARBYTES);
  95   if (align2 + (len + 1) * CHARBYTES >= page_size)
  96     return;
  97
  98   json_element_object_begin (json_ctx);
  99   json_attr_uint (json_ctx, "length", (double) len);
 100   json_attr_uint (json_ctx, "align1", (double) align1);
 101   json_attr_uint (json_ctx, "align2", (double) align2);
 102   json_attr_uint (json_ctx, "result", (double) exp_result);
 103   json_array_begin (json_ctx, "timings");
 104
 105   s1 = (CHAR *)(buf1 + align1);
 106   s2 = (CHAR *)(buf2 + align2);
 107
 108   for (i = 0; i < len; i++)
 109     s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % MAX_CHAR;
 110
 111   if (len)
 112     {
 113       s1[len] = align1;
 114       s2[len] = align2;
 115       s2[len - 1] -= exp_result;
 116     }
 117
 118   FOR_EACH_IMPL (impl, 0)
 119     {
 120       do_one_test (json_ctx, impl, s1, s2, len);
 121     }
 122
 123   json_array_end (json_ctx);
 124   json_element_object_end (json_ctx);
 125 }
 126
 127 int
 128 test_main (void)
 129 {
 130   json_ctx_t json_ctx;
 131   size_t i;
 132
 133   test_init ();
 134
 135   json_init (&json_ctx, 0, stdout);
 136
 137   json_document_begin (&json_ctx);
 138   json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
 139
 140   json_attr_object_begin (&json_ctx, "functions");
 141   json_attr_object_begin (&json_ctx, TEST_NAME);
 142   json_attr_string (&json_ctx, "bench-variant", "default");
 143
 144   json_array_begin (&json_ctx, "ifuncs");
 145   FOR_EACH_IMPL (impl, 0)
 146     json_element_string (&json_ctx, impl->name);
 147   json_array_end (&json_ctx);
 148
 149   json_array_begin (&json_ctx, "results");
 150   for (i = 0; i < 32; ++i)
 151     {
 152       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, 0);
 153       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, 1);
 154       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, -1);
 155     }
 156
 157   for (i = 0; i < 32; ++i)
 158     {
 159       do_test (&json_ctx, 0, 0, i, 0);
 160       do_test (&json_ctx, 0, 0, i, 1);
 161       do_test (&json_ctx, 0, 0, i, -1);
 162       do_test (&json_ctx, 4096 - i, 0, i, 0);
 163       do_test (&json_ctx, 4096 - i, 0, i, 1);
 164       do_test (&json_ctx, 4096 - i, 0, i, -1);
 165     }
 166
 167   for (i = 33; i < 385; i += 32)
 168     {
 169       do_test (&json_ctx, 0, 0, i, 0);
 170       do_test (&json_ctx, 0, 0, i, 1);
 171       do_test (&json_ctx, 0, 0, i, -1);
 172       do_test (&json_ctx, i, 0, i, 0);
 173       do_test (&json_ctx, 0, i, i, 1);
 174       do_test (&json_ctx, i, i, i, -1);
 175     }
 176
 177   for (i = 1; i < 10; ++i)
 178     {
 179       do_test (&json_ctx, 0, 0, 2 << i, 0);
 180       do_test (&json_ctx, 0, 0, 2 << i, 1);
 181       do_test (&json_ctx, 0, 0, 2 << i, -1);
 182       do_test (&json_ctx, (8 - i) * CHARBYTES, (2 * i) * CHARBYTES, 16 << i, 0);
 183       do_test (&json_ctx, 0, 0, 16 << i, 0);
 184       do_test (&json_ctx, 0, 0, 16 << i, 1);
 185       do_test (&json_ctx, 0, 0, 16 << i, -1);
 186       do_test (&json_ctx, i, 0, 2 << i, 0);
 187       do_test (&json_ctx, 0, i, 2 << i, 1);
 188       do_test (&json_ctx, i, i, 2 << i, -1);
 189       do_test (&json_ctx, i, 0, 16 << i, 0);
 190       do_test (&json_ctx, 0, i, 16 << i, 1);
 191       do_test (&json_ctx, i, i, 16 << i, -1);
 192     }
 193
 194   for (i = 1; i < 10; ++i)
 195     {
 196       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 0);
 197       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 1);
 198       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, -1);
 199     }
 200
 201   json_array_end (&json_ctx);
 202   json_attr_object_end (&json_ctx);
 203   json_attr_object_end (&json_ctx);
 204   json_document_end (&json_ctx);
 205
 206   return ret;
 207 }
 208
 209 #include <support/test-driver.c>