blob: a9aa7ad3605c859dbe3ad8f33b09954a02c72700 (
plain)
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
|
/*
* GF-Complete: A Comprehensive Open Source Library for Galois Field Arithmetic
* James S. Plank, Ethan L. Miller, Kevin M. Greenan,
* Benjamin A. Arnold, John A. Burnum, Adam W. Disney, Allen C. McBride.
*
* gf_rand.c -- Random number generator.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include "gf_rand.h"
/* Lifted the "Mother of All" random number generator from http://www.agner.org/random/ */
static uint32_t MOA_X[5];
uint32_t MOA_Random_32() {
uint64_t sum;
sum = (uint64_t)2111111111UL * (uint64_t)MOA_X[3] +
(uint64_t)1492 * (uint64_t)(MOA_X[2]) +
(uint64_t)1776 * (uint64_t)(MOA_X[1]) +
(uint64_t)5115 * (uint64_t)(MOA_X[0]) +
(uint64_t)MOA_X[4];
MOA_X[3] = MOA_X[2]; MOA_X[2] = MOA_X[1]; MOA_X[1] = MOA_X[0];
MOA_X[4] = (uint32_t)(sum >> 32);
MOA_X[0] = (uint32_t)sum;
return MOA_X[0];
}
uint64_t MOA_Random_64() {
uint64_t sum;
sum = MOA_Random_32();
sum <<= 32;
sum |= MOA_Random_32();
return sum;
}
void MOA_Random_128(uint64_t *x) {
x[0] = MOA_Random_64();
x[1] = MOA_Random_64();
return;
}
uint32_t MOA_Random_W(int w, int zero_ok)
{
uint32_t b;
do {
b = MOA_Random_32();
if (w == 31) b &= 0x7fffffff;
if (w < 31) b %= (1 << w);
} while (!zero_ok && b == 0);
return b;
}
void MOA_Seed(uint32_t seed) {
int i;
uint32_t s = seed;
for (i = 0; i < 5; i++) {
s = s * 29943829 - 1;
MOA_X[i] = s;
}
for (i=0; i<19; i++) MOA_Random_32();
}
void MOA_Fill_Random_Region (void *reg, int size)
{
uint32_t *r32;
uint8_t *r8;
int i;
r32 = (uint32_t *) reg;
r8 = (uint8_t *) reg;
for (i = 0; i < size/4; i++) r32[i] = MOA_Random_32();
for (i *= 4; i < size; i++) r8[i] = MOA_Random_W(8, 1);
}
|
