benchtests/bench-memcpy-random.c

   1 /* Measure memcpy performance.
   2    Copyright (C) 2016-2017 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 MIN_PAGE_SIZE 131072
  20 #define TEST_MAIN
  21 #define TEST_NAME "memcpy"
  22 #include "bench-string.h"
  23 #include <assert.h>
  24
  25 IMPL (memcpy, 1)
  26
  27 #define NUM_COPIES 4096
  28
  29 typedef struct { uint16_t size; uint16_t freq; } freq_data_t;
  30 typedef struct { uint8_t align; uint8_t freq; } align_data_t;
  31
  32 #define SIZE_NUM 1024
  33 #define SIZE_MASK (SIZE_NUM-1)
  34 static uint8_t size_arr[SIZE_NUM];
  35
  36 /* Frequency data for memcpy of less than 256 bytes based on SPEC2006.  */
  37 static freq_data_t size_freq[] =
  38 {
  39   {  8, 576}, {104,  94}, { 24,  78}, { 48,  58}, { 32,  48}, { 16,  46},
  40   {  1,  30}, { 96,  12}, { 72,  11}, {216,  11}, {192,   8}, { 12,   7},
  41   {144,   5}, {  2,   4}, { 64,   4}, {120,   4}, {  4,   3}, { 40,   2},
  42   {  7,   2}, {168,   2}, {160,   2}, {128,   1}, {  3,   1}, {  9,   1},
  43   {176,   1}, {240,   1}, { 11,   1}, {  0,   1}, {  5,   1}, {  6,   1},
  44   { 80,   1}, { 52,   1}, {152,   1}, { 10,   1}, { 56,   1}, { 51,   1},
  45   { 14,   1}, {208,   1}, {  0,   0}
  46 };
  47
  48 #define ALIGN_NUM 256
  49 #define ALIGN_MASK (ALIGN_NUM-1)
  50 static uint8_t src_align_arr[ALIGN_NUM];
  51 static uint8_t dst_align_arr[ALIGN_NUM];
  52
  53 /* Source alignment frequency for memcpy based on SPEC2006.  */
  54 static align_data_t src_align_freq[] =
  55 {
  56   {16, 144}, {8, 86}, {3, 23}, {1, 3}, {0, 0}
  57 };
  58
  59 /* Destination alignment frequency for memcpy based on SPEC2006.  */
  60 static align_data_t dst_align_freq[] =
  61 {
  62   {16, 197}, {8, 30}, {3, 23}, {1, 6}, {0, 0}
  63 };
  64
  65 typedef struct
  66 {
  67   uint16_t src;
  68   uint16_t dst;
  69   uint16_t len;
  70 } copy_t;
  71
  72 static copy_t copy[NUM_COPIES];
  73
  74 typedef char *(*proto_t) (char *, const char *, size_t);
  75
  76 static void
  77 init_copy_distribution (void)
  78 {
  79   int i, j, freq, size, n;
  80
  81   for (n = i = 0; (freq = size_freq[i].freq) != 0; i++)
  82     for (j = 0, size = size_freq[i].size; j < freq; j++)
  83       size_arr[n++] = size;
  84   assert (n == SIZE_NUM);
  85
  86   for (n = i = 0; (freq = src_align_freq[i].freq) != 0; i++)
  87     for (j = 0, size = src_align_freq[i].align; j < freq; j++)
  88       src_align_arr[n++] = size - 1;
  89   assert (n == ALIGN_NUM);
  90
  91   for (n = i = 0; (freq = dst_align_freq[i].freq) != 0; i++)
  92     for (j = 0, size = dst_align_freq[i].align; j < freq; j++)
  93       dst_align_arr[n++] = size - 1;
  94   assert (n == ALIGN_NUM);
  95 }
  96
  97
  98 static void
  99 do_one_test (impl_t *impl, char *dst, char *src, copy_t *copy, size_t n)
 100 {
 101   timing_t start, stop, cur;
 102   size_t iters = INNER_LOOP_ITERS * 20;
 103
 104   TIMING_NOW (start);
 105   for (int i = 0; i < iters; ++i)
 106     for (int j = 0; j < n; j++)
 107       CALL (impl, dst + copy[j].dst, src + copy[j].src, copy[j].len);
 108   TIMING_NOW (stop);
 109
 110   TIMING_DIFF (cur, start, stop);
 111
 112   TIMING_PRINT_MEAN ((double) cur, (double) iters);
 113 }
 114
 115 static void
 116 do_test (size_t max_size)
 117 {
 118   for (int i = 0; i < max_size; i++)
 119     buf1[i] = i * 3;
 120
 121   /* Create a random set of copies with the given size and alignment
 122      distributions.  */
 123   for (int i = 0; i < NUM_COPIES; i++)
 124     {
 125       copy[i].dst = (rand () & (max_size - 1)) | 1;
 126       copy[i].dst &= ~dst_align_arr[rand () & ALIGN_MASK];
 127       copy[i].src = (rand () & (max_size - 1)) | 3;
 128       copy[i].src &= ~src_align_arr[rand () & ALIGN_MASK];
 129       copy[i].len = size_arr[rand () & SIZE_MASK];
 130     }
 131
 132   printf ("Memory size %6zd:", max_size);
 133
 134   FOR_EACH_IMPL (impl, 0)
 135     do_one_test (impl, (char *) buf2, (char *) buf1, copy, NUM_COPIES);
 136
 137   putchar ('\n');
 138 }
 139
 140 int
 141 test_main (void)
 142 {
 143   test_init ();
 144   init_copy_distribution ();
 145
 146   printf ("%23s", "");
 147   FOR_EACH_IMPL (impl, 0)
 148     printf ("\t%s", impl->name);
 149   putchar ('\n');
 150
 151   for (int i = 4; i <= 64; i = i * 2)
 152     do_test (i * 1024);
 153
 154   return ret;
 155 }
 156
 157 #include <support/test-driver.c>