benchtests/bench-memset.c

   1 /* Measure memset functions.
   2    Copyright (C) 2013 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 TEST_BZERO
  21 # define TEST_NAME "bzero"
  22 #else
  23 # define TEST_NAME "memset"
  24 #endif
  25 #define MIN_PAGE_SIZE 131072
  26 #include "bench-string.h"
  27
  28 char *simple_memset (char *, int, size_t);
  29
  30 #ifdef TEST_BZERO
  31 typedef void (*proto_t) (char *, size_t);
  32 void simple_bzero (char *, size_t);
  33 void builtin_bzero (char *, size_t);
  34
  35 IMPL (simple_bzero, 0)
  36 IMPL (builtin_bzero, 0)
  37 IMPL (bzero, 1)
  38
  39 void
  40 simple_bzero (char *s, size_t n)
  41 {
  42   simple_memset (s, 0, n);
  43 }
  44
  45 void
  46 builtin_bzero (char *s, size_t n)
  47 {
  48   __builtin_bzero (s, n);
  49 }
  50 #else
  51 typedef char *(*proto_t) (char *, int, size_t);
  52 char *builtin_memset (char *, int, size_t);
  53
  54 IMPL (simple_memset, 0)
  55 IMPL (builtin_memset, 0)
  56 IMPL (memset, 1)
  57
  58 char *
  59 builtin_memset (char *s, int c, size_t n)
  60 {
  61   return __builtin_memset (s, c, n);
  62 }
  63 #endif
  64
  65 char *
  66 inhibit_loop_to_libcall
  67 simple_memset (char *s, int c, size_t n)
  68 {
  69   char *r = s, *end = s + n;
  70   while (r < end)
  71     *r++ = c;
  72   return s;
  73 }
  74
  75 static void
  76 do_one_test (impl_t *impl, char *s, int c __attribute ((unused)), size_t n)
  77 {
  78   size_t i, iters = INNER_LOOP_ITERS;
  79   timing_t start, stop, cur;
  80   char tstbuf[n];
  81 #ifdef TEST_BZERO
  82   simple_bzero (tstbuf, n);
  83   CALL (impl, s, n);
  84   if (memcmp (s, tstbuf, n) != 0)
  85 #else
  86   char *res = CALL (impl, s, c, n);
  87   if (res != s
  88       || simple_memset (tstbuf, c, n) != tstbuf
  89       || memcmp (s, tstbuf, n) != 0)
  90 #endif
  91     {
  92       error (0, 0, "Wrong result in function %s", impl->name);
  93       ret = 1;
  94       return;
  95     }
  96
  97   TIMING_NOW (start);
  98   for (i = 0; i < iters; ++i)
  99     {
 100 #ifdef TEST_BZERO
 101       CALL (impl, s, n);
 102 #else
 103       CALL (impl, s, c, n);
 104 #endif
 105     }
 106   TIMING_NOW (stop);
 107
 108   TIMING_DIFF (cur, start, stop);
 109
 110   TIMING_PRINT_MEAN ((double) cur, (double) iters);
 111 }
 112
 113 static void
 114 do_test (size_t align, int c, size_t len)
 115 {
 116   align &= 7;
 117   if (align + len > page_size)
 118     return;
 119
 120   printf ("Length %4zd, alignment %2zd, c %2d:", len, align, c);
 121
 122   FOR_EACH_IMPL (impl, 0)
 123     do_one_test (impl, (char *) buf1 + align, c, len);
 124
 125   putchar ('\n');
 126 }
 127
 128 int
 129 test_main (void)
 130 {
 131   size_t i;
 132   int c = 0;
 133
 134   test_init ();
 135
 136   printf ("%24s", "");
 137   FOR_EACH_IMPL (impl, 0)
 138     printf ("\t%s", impl->name);
 139   putchar ('\n');
 140
 141 #ifndef TEST_BZERO
 142   for (c = -65; c <= 130; c += 65)
 143 #endif
 144     {
 145       for (i = 0; i < 18; ++i)
 146         do_test (0, c, 1 << i);
 147       for (i = 1; i < 32; ++i)
 148         {
 149           do_test (i, c, i);
 150           if (i & (i - 1))
 151             do_test (0, c, i);
 152         }
 153       do_test (1, c, 14);
 154       do_test (3, c, 1024);
 155       do_test (4, c, 64);
 156       do_test (2, c, 25);
 157     }
 158
 159   return ret;
 160 }
 161
 162 #include "../test-skeleton.c"