forked from rubinius/rubinius
-
Notifications
You must be signed in to change notification settings - Fork 0
/
randomizer.cpp
386 lines (297 loc) · 10.1 KB
/
randomizer.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
#include "vm/config.h"
#include "builtin/randomizer.hpp"
#include "vm.hpp"
#include "objectmemory.hpp"
#include "builtin/bytearray.hpp"
#include "builtin/bignum.hpp"
#include "builtin/class.hpp"
#include "builtin/float.hpp"
#include "builtin/integer.hpp"
#include "util/spinlock.hpp"
#include "object_utils.hpp"
/*
* For gen_seed:
*/
#include <time.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef RBX_WINDOWS
#include <malloc.h>
#include <process.h>
#endif
/*
This is based on random.c from Ruby 1.8.7, which carries the following notice:
This is based on trimmed version of MT19937. To get the original version,
contact <http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html>.
The original copyright notice follows.
A C-program for MT19937, with initialization improved 2002/2/10.
Coded by Takuji Nishimura and Makoto Matsumoto.
This is a faster version by taking Shawn Cokus's optimization,
Matthe Bellew's simplification, Isaku Wada's real version.
Before using, initialize the rng_state by using init_genrand(seed)
or init_by_array(init_key, key_length).
Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. The names of its contributors may not be used to endorse or promote
products derived from this software without specific prior written
permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Any feedback is very welcome.
http://www.math.keio.ac.jp/matumoto/emt.html
email: matumoto@math.keio.ac.jp
*/
/* Period parameters */
#define N 624
#define M 397
#define MATRIX_A 0x9908b0dfUL /* constant vector a */
#define UMASK 0x80000000UL /* most significant w-r bits */
#define LMASK 0x7fffffffUL /* least significant r bits */
#define MIXBITS(u,v) ( ((u) & UMASK) | ((v) & LMASK) )
#define TWIST(u,v) ((MIXBITS(u,v) >> 1) ^ ((v)&1UL ? MATRIX_A : 0UL))
template <typename T>
static T make_mask(T x) {
for(unsigned int i = 1; i < sizeof(T) * 8; i *= 2)
x = x | x >> i;
return x;
}
namespace rubinius {
uint32_t* Randomizer::rng_data() {
return (uint32_t*)rng_state()->raw_bytes();
}
/* initializes rng_state[N] with a seed */
void Randomizer::init_genrand(uint32_t s) {
rbx_spinlock_lock(&lock_);
uint32_t* rng_state = rng_data();
rng_state[0] = s;
for(int j = 1; j < N; j++) {
rng_state[j] = (1812433253UL * (rng_state[j-1] ^ (rng_state[j-1] >> 30)) + j);
/* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
/* In the previous versions, MSBs of the seed affect */
/* only MSBs of the array rng_state[]. */
/* 2002/01/09 modified by Makoto Matsumoto */
}
left_ = 1;
rbx_spinlock_unlock(&lock_);
}
/* initialize by an array with array-length */
/* init_key is the array for initializing keys */
/* key_length is its length */
/* slight change for C++, 2004/2/26 */
void Randomizer::init_by_array(uint32_t init_key[], int key_length) {
init_genrand(19650218UL);
rbx_spinlock_lock(&lock_);
uint32_t* rng_state = rng_data();
int i = 1;
int j = 0;
int k = (N > key_length ? N : key_length);
for(; k; k--) {
rng_state[i] = (rng_state[i] ^ ((rng_state[i-1] ^ (rng_state[i-1] >> 30)) * 1664525UL))
+ init_key[j] + j; /* non linear */
i++;
j++;
if(i >= N) {
rng_state[0] = rng_state[N-1];
i = 1;
}
if(j >= key_length) j = 0;
}
for(k = N-1; k; k--) {
rng_state[i] = (rng_state[i] ^ ((rng_state[i-1] ^ (rng_state[i-1] >> 30)) * 1566083941UL))
- i; /* non linear */
i++;
if(i >= N) {
rng_state[0] = rng_state[N-1];
i = 1;
}
}
rng_state[0] = 0x80000000UL; /* MSB is 1; assuring non-zero initial array */
left_ = 1;
rbx_spinlock_unlock(&lock_);
}
void Randomizer::next_state() {
uint32_t* rng_state = rng_data();
left_ = N;
next_ = 0;
uint32_t* p = rng_state;
int j;
for(j = N-M+1; --j; p++)
*p = p[M] ^ TWIST(p[0], p[1]);
for(j = M; --j; p++)
*p = p[M-N] ^ TWIST(p[0], p[1]);
*p = p[M-N] ^ TWIST(p[0], rng_state[0]);
}
/* generates a random number on [0,0xffffffff]-interval */
uint32_t Randomizer::rb_genrand_int32() {
rbx_spinlock_lock(&lock_);
if(--left_ == 0) next_state();
uint32_t* rng_state = rng_data();
uint32_t y;
y = rng_state[next_++];
rbx_spinlock_unlock(&lock_);
/* Tempering */
y ^= (y >> 11);
y ^= (y << 7) & 0x9d2c5680UL;
y ^= (y << 15) & 0xefc60000UL;
y ^= (y >> 18);
return y;
}
native_uint Randomizer::limited_rand(native_uint limit) {
native_uint mask = make_mask(limit);
retry:
native_uint val = 0;
for(int i = sizeof(native_uint)/4-1; 0 <= i; i--) {
if(mask >> (i * 32)) {
val |= rb_genrand_int32() << (i * 32);
val &= mask;
if(limit < val) goto retry;
}
}
return val;
}
/* generates a random number on [0,1] with 53-bit resolution*/
double Randomizer::rb_genrand_real() {
uint32_t a = rb_genrand_int32()>>5;
uint32_t b = rb_genrand_int32()>>6;
return(a * 67108864.0 + b) * (1.0 / 9007199254740992.0);
}
/* These real versions are due to Isaku Wada, 2002/01/09 added */
void Randomizer::init(STATE) {
GO(randomizer).set(state->new_class("Randomizer", G(object), G(rubinius)));
G(randomizer)->set_object_type(state, RandomizerType);
}
Randomizer* Randomizer::create(STATE) {
Randomizer* r = state->new_object<Randomizer>(G(randomizer));
r->lock_ = RBX_SPINLOCK_INIT;
r->rng_state(state, ByteArray::create(state, N * sizeof(uint32_t)));
return r;
}
Randomizer* Randomizer::allocate(STATE, Object* self) {
Randomizer* randomizer = create(state);
if(Class* cls = try_as<Class>(self)) {
randomizer->klass(state, cls);
}
randomizer->init_genrand(5489UL);
return randomizer;
}
Integer* Randomizer::gen_seed(STATE) {
static int n = 0;
uint32_t seed[] = { 0, 0, 0, 0 };
#ifdef S_ISCHR
int fd;
if((fd = open("/dev/urandom", O_RDONLY
#ifdef O_NONBLOCK
|O_NONBLOCK
#endif
#ifdef O_NOCTTY
|O_NOCTTY
#endif
#ifdef O_NOFOLLOW
|O_NOFOLLOW
#endif
)) >= 0) {
struct stat statbuf;
if(fstat(fd, &statbuf) == 0 && S_ISCHR(statbuf.st_mode)) {
/* If this fails, we're no worse off than if it hadn't opened to
* begin with */
if(read(fd, seed, 4 * sizeof(uint32_t)) < 0) {
seed[0] = 57;
seed[1] = 0x83221ab;
seed[2] = 0;
seed[3] = 0;
}
}
close(fd);
}
#endif
struct timeval tv;
gettimeofday(&tv, 0);
seed[0] ^= tv.tv_usec;
seed[1] ^= tv.tv_sec;
seed[2] ^= getpid() ^ (n++ << 16);
seed[3] ^= (uint32_t)(uintptr_t)&seed;
return Bignum::from_array(state, seed, 4);
}
Object* Randomizer::seed(STATE, Integer* seed) {
Bignum* big;
size_t longs;
uint32_t* data;
if(!seed->fixnum_p())
seed = as<Bignum>(seed)->abs(state);
if(seed->fixnum_p()) {
native_uint s = seed->to_native();
// Remove the sign bit, for no good reason... but that's what MRI
// does.
s &= ~((native_uint)1 << (sizeof(native_uint) * 8 - 1));
if(s <= 0xffffffffUL) {
init_genrand((uint32_t)s);
return Qnil;
}
longs = sizeof(native_uint) / 4;
data = (uint32_t*)alloca(longs * 4);
for(unsigned int i = 0; i < longs; i++)
data[i] = (uint32_t)(s >> (i * 32));
init_by_array(data, longs);
} else {
big = as<Bignum>(seed);
longs = big->into_array(state, NULL, 0);
data = (uint32_t*)alloca(longs * 4);
big->into_array(state, data, longs);
init_by_array(data, longs);
}
return Qnil;
}
Integer* Randomizer::rand_int(STATE, Integer* max) {
if(max->fixnum_p()) {
native_uint max_i = max->to_native();
native_uint result = limited_rand(max_i);
return Integer::from(state, result);
}
Bignum* max_big = as<Bignum>(max);
size_t longs = max_big->into_array(state, NULL, 0);
uint32_t* max_data = (uint32_t*)alloca(longs * 4);
max_big->into_array(state, max_data, longs);
uint32_t* result_data = (uint32_t*)alloca(longs * 4);
retry:
uint32_t mask = 0;
int boundary = 1;
for(int i = longs - 1; i >= 0; i--) {
uint32_t rnd;
uint32_t lim = max_data[i];
mask = mask ? 0xffffffff : make_mask(lim);
if(mask) {
rnd = rb_genrand_int32() & mask;
if(boundary) {
if(lim < rnd) goto retry;
if(rnd < lim) boundary = 0;
}
} else {
rnd = 0;
}
result_data[i] = rnd;
}
return Bignum::from_array(state, result_data, longs);
}
Float* Randomizer::rand_float(STATE) {
return Float::create(state, rb_genrand_real());
}
}