1 /* 2 * Copyright 2012 Siarhei Siamashka <siarhei.siamashka (at) gmail.com> 3 * 4 * Based on the public domain implementation of small noncryptographic PRNG 5 * authored by Bob Jenkins: http://burtleburtle.net/bob/rand/smallprng.html 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a 8 * copy of this software and associated documentation files (the "Software"), 9 * to deal in the Software without restriction, including without limitation 10 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 11 * and/or sell copies of the Software, and to permit persons to whom the 12 * Software is furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the next 15 * paragraph) shall be included in all copies or substantial portions of the 16 * Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 23 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 24 * DEALINGS IN THE SOFTWARE. 25 */ 26 27 #include <assert.h> 28 #include <stdlib.h> 29 #include "utils-prng.h" 30 #include "utils.h" 31 32 /* The original code from http://www.burtleburtle.net/bob/rand/smallprng.html */ 33 34 typedef uint32_t u4; 35 typedef struct ranctx { u4 a; u4 b; u4 c; u4 d; } ranctx; 36 37 #define rot(x,k) (((x)<<(k))|((x)>>(32-(k)))) 38 u4 ranval( ranctx *x ) { 39 u4 e = x->a - rot(x->b, 27); 40 x->a = x->b ^ rot(x->c, 17); 41 x->b = x->c + x->d; 42 x->c = x->d + e; 43 x->d = e + x->a; 44 return x->d; 45 } 46 47 void raninit( ranctx *x, u4 seed ) { 48 u4 i; 49 x->a = 0xf1ea5eed, x->b = x->c = x->d = seed; 50 for (i=0; i<20; ++i) { 51 (void)ranval(x); 52 } 53 } 54 55 /*****************************************************************************/ 56 57 #define BUFSIZE (8 * 1024 * 1024) 58 #define N 50 59 60 void bench (void) 61 { 62 double t1, t2; 63 int i; 64 prng_t prng; 65 uint8_t *buf = aligned_malloc (16, BUFSIZE + 1); 66 67 prng_srand_r (&prng, 1234); 68 t1 = gettime(); 69 for (i = 0; i < N; i++) 70 prng_randmemset_r (&prng, buf, BUFSIZE, 0); 71 t2 = gettime(); 72 printf ("aligned randmemset : %.2f MB/s\n", 73 (double)BUFSIZE * N / 1000000. / (t2 - t1)); 74 75 t1 = gettime(); 76 for (i = 0; i < N; i++) 77 prng_randmemset_r (&prng, buf + 1, BUFSIZE, 0); 78 t2 = gettime(); 79 printf ("unaligned randmemset : %.2f MB/s\n", 80 (double)BUFSIZE * N / 1000000. / (t2 - t1)); 81 82 t1 = gettime(); 83 for (i = 0; i < N; i++) 84 { 85 prng_randmemset_r (&prng, buf, BUFSIZE, RANDMEMSET_MORE_00_AND_FF); 86 } 87 t2 = gettime (); 88 printf ("aligned randmemset (more 00 and FF) : %.2f MB/s\n", 89 (double)BUFSIZE * N / 1000000. / (t2 - t1)); 90 91 t1 = gettime(); 92 for (i = 0; i < N; i++) 93 { 94 prng_randmemset_r (&prng, buf + 1, BUFSIZE, RANDMEMSET_MORE_00_AND_FF); 95 } 96 t2 = gettime (); 97 printf ("unaligned randmemset (more 00 and FF) : %.2f MB/s\n", 98 (double)BUFSIZE * N / 1000000. / (t2 - t1)); 99 100 free (buf); 101 } 102 103 #define SMALLBUFSIZE 100 104 105 int main (int argc, char *argv[]) 106 { 107 const uint32_t ref_crc[RANDMEMSET_MORE_00_AND_FF + 1] = 108 { 109 0xBA06763D, 0x103FC550, 0x8B59ABA5, 0xD82A0F39, 110 0xD2321099, 0xFD8C5420, 0xD3B7C42A, 0xFC098093, 111 0x85E01DE0, 0x6680F8F7, 0x4D32DD3C, 0xAE52382B, 112 0x149E6CB5, 0x8B336987, 0x15DCB2B3, 0x8A71B781 113 }; 114 uint32_t crc1, crc2; 115 uint32_t ref, seed, seed0, seed1, seed2, seed3; 116 prng_rand_128_data_t buf; 117 uint8_t *bytebuf = aligned_malloc(16, SMALLBUFSIZE + 1); 118 ranctx x; 119 prng_t prng; 120 prng_randmemset_flags_t flags; 121 122 if (argc > 1 && strcmp(argv[1], "-bench") == 0) 123 { 124 bench (); 125 return 0; 126 } 127 128 /* basic test */ 129 raninit (&x, 0); 130 prng_srand_r (&prng, 0); 131 assert (ranval (&x) == prng_rand_r (&prng)); 132 133 /* test for simd code */ 134 seed = 0; 135 prng_srand_r (&prng, seed); 136 seed0 = (seed = seed * 1103515245 + 12345); 137 seed1 = (seed = seed * 1103515245 + 12345); 138 seed2 = (seed = seed * 1103515245 + 12345); 139 seed3 = (seed = seed * 1103515245 + 12345); 140 prng_rand_128_r (&prng, &buf); 141 142 raninit (&x, seed0); 143 ref = ranval (&x); 144 assert (ref == buf.w[0]); 145 146 raninit (&x, seed1); 147 ref = ranval (&x); 148 assert (ref == buf.w[1]); 149 150 raninit (&x, seed2); 151 ref = ranval (&x); 152 assert (ref == buf.w[2]); 153 154 raninit (&x, seed3); 155 ref = ranval (&x); 156 assert (ref == buf.w[3]); 157 158 /* test for randmemset */ 159 for (flags = 0; flags <= RANDMEMSET_MORE_00_AND_FF; flags++) 160 { 161 prng_srand_r (&prng, 1234); 162 prng_randmemset_r (&prng, bytebuf, 16, flags); 163 prng_randmemset_r (&prng, bytebuf + 16, SMALLBUFSIZE - 17, flags); 164 crc1 = compute_crc32 (0, bytebuf, SMALLBUFSIZE - 1); 165 prng_srand_r (&prng, 1234); 166 prng_randmemset_r (&prng, bytebuf + 1, SMALLBUFSIZE - 1, flags); 167 crc2 = compute_crc32 (0, bytebuf + 1, SMALLBUFSIZE - 1); 168 assert (ref_crc[flags] == crc1); 169 assert (ref_crc[flags] == crc2); 170 } 171 172 free (bytebuf); 173 174 return 0; 175 } 176
