prng-test.c revision 1176bdada62cabc6ec4b0308a930e83b679d5d36 
1/*
2 * Copyright © 2012 Siarhei Siamashka <siarhei.siamashka@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
34typedef uint32_t u4;
35typedef struct ranctx { u4 a; u4 b; u4 c; u4 d; } ranctx;
36
37#define rot(x,k) (((x)<<(k))|((x)>>(32-(k))))
38u4 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
47void 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
60void 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
105int 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