benchtests/bench-memcpy-random.c

   1 /* Measure memcpy performance.
   2    Copyright (C) 2016-2018 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 MIN_PAGE_SIZE 131072
  20 #define TEST_MAIN
  21 #define TEST_NAME "memcpy"
  22 #include "bench-string.h"
  23 #include <assert.h>
  24 #include "json-lib.h"
  25
  26 IMPL (memcpy, 1)
  27
  28 #define NUM_COPIES 4096
  29
  30 typedef struct { uint16_t size; uint16_t freq; } freq_data_t;
  31 typedef struct { uint8_t align; uint8_t freq; } align_data_t;
  32
  33 #define SIZE_NUM 1024
  34 #define SIZE_MASK (SIZE_NUM-1)
  35 static uint8_t size_arr[SIZE_NUM];
  36
  37 /* Frequency data for memcpy of less than 256 bytes based on SPEC2006.  */
  38 static freq_data_t size_freq[] =
  39 {
  40   {  8, 576}, {104,  94}, { 24,  78}, { 48,  58}, { 32,  48}, { 16,  46},
  41   {  1,  30}, { 96,  12}, { 72,  11}, {216,  11}, {192,   8}, { 12,   7},
  42   {144,   5}, {  2,   4}, { 64,   4}, {120,   4}, {  4,   3}, { 40,   2},
  43   {  7,   2}, {168,   2}, {160,   2}, {128,   1}, {  3,   1}, {  9,   1},
  44   {176,   1}, {240,   1}, { 11,   1}, {  0,   1}, {  5,   1}, {  6,   1},
  45   { 80,   1}, { 52,   1}, {152,   1}, { 10,   1}, { 56,   1}, { 51,   1},
  46   { 14,   1}, {208,   1}, {  0,   0}
  47 };
  48
  49 #define ALIGN_NUM 256
  50 #define ALIGN_MASK (ALIGN_NUM-1)
  51 static uint8_t src_align_arr[ALIGN_NUM];
  52 static uint8_t dst_align_arr[ALIGN_NUM];
  53
  54 /* Source alignment frequency for memcpy based on SPEC2006.  */
  55 static align_data_t src_align_freq[] =
  56 {
  57   {16, 144}, {8, 86}, {3, 23}, {1, 3}, {0, 0}
  58 };
  59
  60 /* Destination alignment frequency for memcpy based on SPEC2006.  */
  61 static align_data_t dst_align_freq[] =
  62 {
  63   {16, 197}, {8, 30}, {3, 23}, {1, 6}, {0, 0}
  64 };
  65
  66 typedef struct
  67 {
  68   uint16_t src;
  69   uint16_t dst;
  70   uint16_t len;
  71 } copy_t;
  72
  73 static copy_t copy[NUM_COPIES];
  74
  75 typedef char *(*proto_t) (char *, const char *, size_t);
  76
  77 static void
  78 init_copy_distribution (void)
  79 {
  80   int i, j, freq, size, n;
  81
  82   for (n = i = 0; (freq = size_freq[i].freq) != 0; i++)
  83     for (j = 0, size = size_freq[i].size; j < freq; j++)
  84       size_arr[n++] = size;
  85   assert (n == SIZE_NUM);
  86
  87   for (n = i = 0; (freq = src_align_freq[i].freq) != 0; i++)
  88     for (j = 0, size = src_align_freq[i].align; j < freq; j++)
  89       src_align_arr[n++] = size - 1;
  90   assert (n == ALIGN_NUM);
  91
  92   for (n = i = 0; (freq = dst_align_freq[i].freq) != 0; i++)
  93     for (j = 0, size = dst_align_freq[i].align; j < freq; j++)
  94       dst_align_arr[n++] = size - 1;
  95   assert (n == ALIGN_NUM);
  96 }
  97
  98
  99 static void
 100 do_one_test (json_ctx_t *json_ctx, impl_t *impl, char *dst, char *src,
 101              copy_t *copy, size_t n)
 102 {
 103   timing_t start, stop, cur;
 104   size_t iters = INNER_LOOP_ITERS * 20;
 105
 106   TIMING_NOW (start);
 107   for (int i = 0; i < iters; ++i)
 108     for (int j = 0; j < n; j++)
 109       CALL (impl, dst + copy[j].dst, src + copy[j].src, copy[j].len);
 110   TIMING_NOW (stop);
 111
 112   TIMING_DIFF (cur, start, stop);
 113
 114   json_element_double (json_ctx, (double) cur / (double) iters);
 115 }
 116
 117 static void
 118 do_test (json_ctx_t *json_ctx, size_t max_size)
 119 {
 120   for (int i = 0; i < max_size; i++)
 121     buf1[i] = i * 3;
 122
 123   /* Create a random set of copies with the given size and alignment
 124      distributions.  */
 125   for (int i = 0; i < NUM_COPIES; i++)
 126     {
 127       copy[i].dst = (rand () & (max_size - 1)) | 1;
 128       copy[i].dst &= ~dst_align_arr[rand () & ALIGN_MASK];
 129       copy[i].src = (rand () & (max_size - 1)) | 3;
 130       copy[i].src &= ~src_align_arr[rand () & ALIGN_MASK];
 131       copy[i].len = size_arr[rand () & SIZE_MASK];
 132     }
 133
 134   json_element_object_begin (json_ctx);
 135   json_attr_uint (json_ctx, "max-size", (double) max_size);
 136   json_array_begin (json_ctx, "timings");
 137
 138   FOR_EACH_IMPL (impl, 0)
 139     do_one_test (json_ctx, impl, (char *) buf2, (char *) buf1, copy, NUM_COPIES);
 140
 141   json_array_end (json_ctx);
 142   json_element_object_end (json_ctx);
 143 }
 144
 145 int
 146 test_main (void)
 147 {
 148   json_ctx_t json_ctx;
 149
 150   test_init ();
 151   init_copy_distribution ();
 152
 153   json_init (&json_ctx, 0, stdout);
 154
 155   json_document_begin (&json_ctx);
 156   json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
 157
 158   json_attr_object_begin (&json_ctx, "functions");
 159   json_attr_object_begin (&json_ctx, TEST_NAME);
 160   json_attr_string (&json_ctx, "bench-variant", "random");
 161
 162   json_array_begin (&json_ctx, "ifuncs");
 163   FOR_EACH_IMPL (impl, 0)
 164     json_element_string (&json_ctx, impl->name);
 165   json_array_end (&json_ctx);
 166
 167   json_array_begin (&json_ctx, "results");
 168   for (int i = 4; i <= 64; i = i * 2)
 169     do_test (&json_ctx, i * 1024);
 170
 171   json_array_end (&json_ctx);
 172   json_attr_object_end (&json_ctx);
 173   json_attr_object_end (&json_ctx);
 174   json_document_end (&json_ctx);
 175
 176   return ret;
 177 }
 178
 179 #include <support/test-driver.c>