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
|
/*
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 state by using init_genrand(mt, seed)
or init_by_array(mt, 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 0x9908b0dfU /* constant vector a */
#define UMASK 0x80000000U /* most significant w-r bits */
#define LMASK 0x7fffffffU /* least significant r bits */
#define MIXBITS(u,v) ( ((u) & UMASK) | ((v) & LMASK) )
#define TWIST(u,v) ((MIXBITS((u),(v)) >> 1) ^ ((v)&1U ? MATRIX_A : 0U))
enum {MT_MAX_STATE = N};
struct MT {
/* assume int is enough to store 32bits */
uint32_t state[N]; /* the array for the state vector */
uint32_t *next;
int left;
};
#define genrand_initialized(mt) ((mt)->next != 0)
#define uninit_genrand(mt) ((mt)->next = 0)
NO_SANITIZE("unsigned-integer-overflow", static void init_genrand(struct MT *mt, unsigned int s));
NO_SANITIZE("unsigned-integer-overflow", static void init_by_array(struct MT *mt, const uint32_t init_key[], int key_length));
/* initializes state[N] with a seed */
static void
init_genrand(struct MT *mt, unsigned int s)
{
int j;
mt->state[0] = s & 0xffffffffU;
for (j=1; j<N; j++) {
mt->state[j] = (1812433253U * (mt->state[j-1] ^ (mt->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 state[]. */
/* 2002/01/09 modified by Makoto Matsumoto */
mt->state[j] &= 0xffffffff; /* for >32 bit machines */
}
mt->left = 1;
mt->next = mt->state + N;
}
/* 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 */
static void
init_by_array(struct MT *mt, const uint32_t init_key[], int key_length)
{
int i, j, k;
init_genrand(mt, 19650218U);
i=1; j=0;
k = (N>key_length ? N : key_length);
for (; k; k--) {
mt->state[i] = (mt->state[i] ^ ((mt->state[i-1] ^ (mt->state[i-1] >> 30)) * 1664525U))
+ init_key[j] + j; /* non linear */
mt->state[i] &= 0xffffffffU; /* for WORDSIZE > 32 machines */
i++; j++;
if (i>=N) { mt->state[0] = mt->state[N-1]; i=1; }
if (j>=key_length) j=0;
}
for (k=N-1; k; k--) {
mt->state[i] = (mt->state[i] ^ ((mt->state[i-1] ^ (mt->state[i-1] >> 30)) * 1566083941U))
- i; /* non linear */
mt->state[i] &= 0xffffffffU; /* for WORDSIZE > 32 machines */
i++;
if (i>=N) { mt->state[0] = mt->state[N-1]; i=1; }
}
mt->state[0] = 0x80000000U; /* MSB is 1; assuring non-zero initial array */
}
static void
next_state(struct MT *mt)
{
uint32_t *p = mt->state;
int j;
mt->left = N;
mt->next = mt->state;
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], mt->state[0]);
}
/* generates a random number on [0,0xffffffff]-interval */
static unsigned int
genrand_int32(struct MT *mt)
{
/* mt must be initialized */
unsigned int y;
if (--mt->left <= 0) next_state(mt);
y = *mt->next++;
/* Tempering */
y ^= (y >> 11);
y ^= (y << 7) & 0x9d2c5680;
y ^= (y << 15) & 0xefc60000;
y ^= (y >> 18);
return y;
}
|
