benchtests/bench-memcmp.c

   1 /* Measure memcmp 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 #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
  28 # define SIMPLE_MEMCMP simple_wmemcmp
  29 int
  30 simple_wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
  31 {
  32   int ret = 0;
  33   /* Warning!
  34         wmemcmp has to use SIGNED comparison for elements.
  35         memcmp has to use UNSIGNED comparison for elemnts.
  36   */
  37   while (n-- && (ret = *s1 < *s2 ? -1 : *s1 == *s2 ? 0 : 1) == 0) {s1++; s2++;}
  38   return ret;
  39 }
  40 #else
  41 # include <limits.h>
  42
  43 # define SIMPLE_MEMCMP simple_memcmp
  44
  45 int
  46 simple_memcmp (const char *s1, const char *s2, size_t n)
  47 {
  48   int ret = 0;
  49
  50   while (n-- && (ret = *(unsigned char *) s1++ - *(unsigned char *) s2++) == 0);
  51   return ret;
  52 }
  53 #endif
  54
  55 # include "json-lib.h"
  56
  57 typedef int (*proto_t) (const CHAR *, const CHAR *, size_t);
  58
  59 IMPL (SIMPLE_MEMCMP, 0)
  60 IMPL (MEMCMP, 1)
  61
  62 static void
  63 do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s1,
  64              const CHAR *s2, size_t len, int exp_result)
  65 {
  66   size_t i, iters = INNER_LOOP_ITERS8;
  67   timing_t start, stop, cur;
  68
  69   TIMING_NOW (start);
  70   for (i = 0; i < iters; ++i)
  71     {
  72       CALL (impl, s1, s2, len);
  73     }
  74   TIMING_NOW (stop);
  75
  76   TIMING_DIFF (cur, start, stop);
  77
  78   json_element_double (json_ctx, (double) cur / (double) iters);
  79 }
  80
  81 static void
  82 do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
  83          int exp_result)
  84 {
  85   size_t i;
  86   CHAR *s1, *s2;
  87
  88   if (len == 0)
  89     return;
  90
  91   align1 &= (4096 - CHARBYTES);
  92   if (align1 + (len + 1) * CHARBYTES >= page_size)
  93     return;
  94
  95   align2 &= (4096 - CHARBYTES);
  96   if (align2 + (len + 1) * CHARBYTES >= page_size)
  97     return;
  98
  99   json_element_object_begin (json_ctx);
 100   json_attr_uint (json_ctx, "length", (double) len);
 101   json_attr_uint (json_ctx, "align1", (double) align1);
 102   json_attr_uint (json_ctx, "align2", (double) align2);
 103   json_attr_uint (json_ctx, "result", (double) exp_result);
 104   json_array_begin (json_ctx, "timings");
 105
 106   FOR_EACH_IMPL (impl, 0)
 107     {
 108       s1 = (CHAR *) (buf1 + align1);
 109       s2 = (CHAR *) (buf2 + align2);
 110
 111       for (i = 0; i < len; i++)
 112         s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % MAX_CHAR;
 113
 114       s1[len] = align1;
 115       s2[len] = align2;
 116       s2[len - 1] -= exp_result;
 117
 118       do_one_test (json_ctx, impl, s1, s2, len, exp_result);
 119       alloc_bufs ();
 120     }
 121
 122   json_array_end (json_ctx);
 123   json_element_object_end (json_ctx);
 124 }
 125
 126 int
 127 test_main (void)
 128 {
 129   json_ctx_t json_ctx;
 130   size_t i;
 131
 132   test_init ();
 133
 134   json_init (&json_ctx, 0, stdout);
 135
 136   json_document_begin (&json_ctx);
 137   json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
 138
 139   json_attr_object_begin (&json_ctx, "functions");
 140   json_attr_object_begin (&json_ctx, TEST_NAME);
 141   json_attr_string (&json_ctx, "bench-variant", "default");
 142
 143   json_array_begin (&json_ctx, "ifuncs");
 144   FOR_EACH_IMPL (impl, 0)
 145     json_element_string (&json_ctx, impl->name);
 146   json_array_end (&json_ctx);
 147
 148   json_array_begin (&json_ctx, "results");
 149   for (i = 1; i < 32; ++i)
 150     {
 151       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, 0);
 152       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, 1);
 153       do_test (&json_ctx, i * CHARBYTES, i * CHARBYTES, i, -1);
 154     }
 155
 156   for (i = 0; i < 32; ++i)
 157     {
 158       do_test (&json_ctx, 0, 0, i, 0);
 159       do_test (&json_ctx, 0, 0, i, 1);
 160       do_test (&json_ctx, 0, 0, i, -1);
 161       do_test (&json_ctx, 4096 - i, 0, i, 0);
 162       do_test (&json_ctx, 4096 - i, 0, i, 1);
 163       do_test (&json_ctx, 4096 - i, 0, i, -1);
 164     }
 165
 166   for (i = 33; i < 385; i += 32)
 167     {
 168       do_test (&json_ctx, 0, 0, i, 0);
 169       do_test (&json_ctx, 0, 0, i, 1);
 170       do_test (&json_ctx, 0, 0, i, -1);
 171       do_test (&json_ctx, i, 0, i, 0);
 172       do_test (&json_ctx, 0, i, i, 1);
 173       do_test (&json_ctx, i, i, i, -1);
 174     }
 175
 176   for (i = 1; i < 10; ++i)
 177     {
 178       do_test (&json_ctx, 0, 0, 2 << i, 0);
 179       do_test (&json_ctx, 0, 0, 2 << i, 1);
 180       do_test (&json_ctx, 0, 0, 2 << i, -1);
 181       do_test (&json_ctx, (8 - i) * CHARBYTES, (2 * i) * CHARBYTES, 16 << i, 0);
 182       do_test (&json_ctx, 0, 0, 16 << i, 0);
 183       do_test (&json_ctx, 0, 0, 16 << i, 1);
 184       do_test (&json_ctx, 0, 0, 16 << i, -1);
 185       do_test (&json_ctx, i, 0, 2 << i, 0);
 186       do_test (&json_ctx, 0, i, 2 << i, 1);
 187       do_test (&json_ctx, i, i, 2 << i, -1);
 188       do_test (&json_ctx, i, 0, 16 << i, 0);
 189       do_test (&json_ctx, 0, i, 16 << i, 1);
 190       do_test (&json_ctx, i, i, 16 << i, -1);
 191     }
 192
 193   for (i = 1; i < 10; ++i)
 194     {
 195       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 0);
 196       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, 1);
 197       do_test (&json_ctx, i * CHARBYTES, 2 * (i * CHARBYTES), 8 << i, -1);
 198     }
 199
 200   json_array_end (&json_ctx);
 201   json_attr_object_end (&json_ctx);
 202   json_attr_object_end (&json_ctx);
 203   json_document_end (&json_ctx);
 204
 205   return ret;
 206 }
 207
 208 #include <support/test-driver.c>