string: Add memcpy benchmark

Add memcpy benchmark based on size and alignment distribution of SPEC2017.

1 files changed, 186 insertions, 0 deletions

diff --git a/string/bench/memcpy.c b/string/bench/memcpy.c
new file mode 100644
index 0000000..67c1b88
--- /dev/null
+++ b/string/bench/memcpy.c
@@ -0,0 +1,186 @@
+/*
+ * memcpy benchmark.
+ *
+ * Copyright (c) 2020, Arm Limited.
+ * SPDX-License-Identifier: MIT
+ */
+
+#define _GNU_SOURCE
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include "stringlib.h"
+#include "benchlib.h"
+
+#define ITERS 2000
+#define MAX_COPIES 8192
+#define SIZE (256*1024)
+
+static uint8_t a[SIZE + 4096] __attribute__((__aligned__(64)));
+static uint8_t b[SIZE + 4096] __attribute__((__aligned__(64)));
+
+#define F(x) {#x, x},
+
+static const struct fun
+{
+  const char *name;
+  void *(*fun)(void *, const void *, size_t);
+} funtab[] =
+{
+  F(memcpy)
+#if __aarch64__
+  F(__memcpy_aarch64)
+# if __ARM_NEON
+  F(__memcpy_aarch64_simd)
+# endif
+#elif __arm__
+  F(__memcpy_arm)
+#endif
+#undef F
+  {0, 0}
+};
+
+typedef struct { uint16_t size; uint16_t freq; } freq_data_t;
+typedef struct { uint8_t align; uint16_t freq; } align_data_t;
+
+#define SIZE_NUM 65536
+#define SIZE_MASK (SIZE_NUM-1)
+static uint8_t size_arr[SIZE_NUM];
+
+/* Frequency data for memcpy of less than 4096 bytes based on SPEC2017.  */
+static freq_data_t size_freq[] =
+{
+{32,22320}, { 16,9554}, {  8,8915}, {152,5327}, {  4,2159}, {292,2035},
+{ 12,1608}, { 24,1343}, {1152,895}, {144, 813}, {884, 733}, {284, 721},
+{120, 661}, {  2, 649}, {882, 550}, {  5, 475}, {  7, 461}, {108, 460},
+{ 10, 361}, {  9, 361}, {  6, 334}, {  3, 326}, {464, 308}, {2048,303},
+{  1, 298}, { 64, 250}, { 11, 197}, {296, 194}, { 68, 187}, { 15, 185},
+{192, 184}, {1764,183}, { 13, 173}, {560, 126}, {160, 115}, {288,  96},
+{104,  96}, {1144, 83}, { 18,  80}, { 23,  78}, { 40,  77}, { 19,  68},
+{ 48,  63}, { 17,  57}, { 72,  54}, {1280, 51}, { 20,  49}, { 28,  47},
+{ 22,  46}, {640,  45}, { 25,  41}, { 14,  40}, { 56,  37}, { 27,  35},
+{ 35,  33}, {384,  33}, { 29,  32}, { 80,  30}, {4095, 22}, {232,  22},
+{ 36,  19}, {184,  17}, { 21,  17}, {256,  16}, { 44,  15}, { 26,  15},
+{ 31,  14}, { 88,  14}, {176,  13}, { 33,  12}, {1024, 12}, {208,  11},
+{ 62,  11}, {128,  10}, {704,  10}, {324,  10}, { 96,  10}, { 60,   9},
+{136,   9}, {124,   9}, { 34,   8}, { 30,   8}, {480,   8}, {1344,  8},
+{273,   7}, {520,   7}, {112,   6}, { 52,   6}, {344,   6}, {336,   6},
+{504,   5}, {168,   5}, {424,   5}, {  0,   4}, { 76,   3}, {200,   3},
+{512,   3}, {312,   3}, {240,   3}, {960,   3}, {264,   2}, {672,   2},
+{ 38,   2}, {328,   2}, { 84,   2}, { 39,   2}, {216,   2}, { 42,   2},
+{ 37,   2}, {1608,  2}, { 70,   2}, { 46,   2}, {536,   2}, {280,   1},
+{248,   1}, { 47,   1}, {1088,  1}, {1288,  1}, {224,   1}, { 41,   1},
+{ 50,   1}, { 49,   1}, {808,   1}, {360,   1}, {440,   1}, { 43,   1},
+{ 45,   1}, { 78,   1}, {968,   1}, {392,   1}, { 54,   1}, { 53,   1},
+{ 59,   1}, {376,   1}, {664,   1}, { 58,   1}, {272,   1}, { 66,   1},
+{2688,  1}, {472,   1}, {568,   1}, {720,   1}, { 51,   1}, { 63,   1},
+{ 86,   1}, {496,   1}, {776,   1}, { 57,   1}, {680,   1}, {792,   1},
+{122,   1}, {760,   1}, {824,   1}, {552,   1}, { 67,   1}, {456,   1},
+{984,   1}, { 74,   1}, {408,   1}, { 75,   1}, { 92,   1}, {576,   1},
+{116,   1}, { 65,   1}, {117,   1}, { 82,   1}, {352,   1}, { 55,   1},
+{100,   1}, { 90,   1}, {696,   1}, {111,   1}, {880,   1}, { 79,   1},
+{488,   1}, { 61,   1}, {114,   1}, { 94,   1}, {1032,  1}, { 98,   1},
+{ 87,   1}, {584,   1}, { 85,   1}, {648,   1}, {0, 0}
+};
+
+#define ALIGN_NUM 1024
+#define ALIGN_MASK (ALIGN_NUM-1)
+static uint8_t src_align_arr[ALIGN_NUM];
+static uint8_t dst_align_arr[ALIGN_NUM];
+
+/* Source alignment frequency for memcpy based on SPEC2017.  */
+static align_data_t src_align_freq[] =
+{
+  {8, 300}, {16, 292}, {32, 168}, {64, 153}, {4, 79}, {2, 14}, {1, 18}, {0, 0}
+};
+
+static align_data_t dst_align_freq[] =
+{
+  {8, 265}, {16, 263}, {64, 209}, {32, 174}, {4, 90}, {2, 10}, {1, 13}, {0, 0}
+};
+
+typedef struct
+{
+  uint64_t src : 24;
+  uint64_t dst : 24;
+  uint64_t len : 16;
+} copy_t;
+
+static copy_t copy[MAX_COPIES];
+
+typedef char *(*proto_t) (char *, const char *, size_t);
+
+static void
+init_copy_distribution (void)
+{
+  int i, j, freq, size, n;
+
+  for (n = i = 0; (freq = size_freq[i].freq) != 0; i++)
+    for (j = 0, size = size_freq[i].size; j < freq; j++)
+      size_arr[n++] = size;
+  assert (n == SIZE_NUM);
+
+  for (n = i = 0; (freq = src_align_freq[i].freq) != 0; i++)
+    for (j = 0, size = src_align_freq[i].align; j < freq; j++)
+      src_align_arr[n++] = size - 1;
+  assert (n == ALIGN_NUM);
+
+  for (n = i = 0; (freq = dst_align_freq[i].freq) != 0; i++)
+    for (j = 0, size = dst_align_freq[i].align; j < freq; j++)
+      dst_align_arr[n++] = size - 1;
+  assert (n == ALIGN_NUM);
+}
+
+static size_t
+init_copies (size_t max_size)
+{
+  size_t total = 0;
+  /* Create a random set of copies with the given size and alignment
+     distributions.  */
+  for (int i = 0; i < MAX_COPIES; i++)
+    {
+      copy[i].dst = (rand32 (0) & (max_size - 1));
+      copy[i].dst &= ~dst_align_arr[rand32 (0) & ALIGN_MASK];
+      copy[i].src = (rand32 (0) & (max_size - 1));
+      copy[i].src &= ~src_align_arr[rand32 (0) & ALIGN_MASK];
+      copy[i].len = size_arr[rand32 (0) & SIZE_MASK];
+      total += copy[i].len;
+    }
+
+  return total;
+}
+
+int main (void)
+{
+  init_copy_distribution ();
+
+  memset (a, 1, sizeof (a));
+  memset (b, 2, sizeof (b));
+
+  for (int f = 0; funtab[f].name != 0; f++)
+    {
+      size_t total = 0;
+      uint64_t tsum = 0;
+      printf("%22s ", funtab[f].name);
+      rand32 (0x12345678);
+
+      for (int size = 16384; size <= SIZE; size *= 2)
+	{
+	  total += init_copies (size);
+
+	  for (int c = 0; c < MAX_COPIES; c++)
+	    funtab[f].fun (b + copy[c].dst, a + copy[c].src, copy[c].len);
+
+	  uint64_t t = clock_get_ns ();
+	  for (int i = 0; i < ITERS; i++)
+	    for (int c = 0; c < MAX_COPIES; c++)
+	      funtab[f].fun (b + copy[c].dst, a + copy[c].src, copy[c].len);
+	  t = clock_get_ns () - t;
+	  tsum += t;
+	  printf("%dK: %.1fms, ", size / 1024, t / 1000000.0);
+	}
+      printf("\b\b (%.2fb/ns)\n", (double)total * ITERS / tsum);
+    }
+  return 0;
+}