random.cc (4395:9acb011a6c35) random.cc (5190:fc46e0d647b6)
1/*
2 * Copyright (c) 2003-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;

--- 15 unchanged lines hidden (view full) ---

24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Nathan Binkert
29 * Ali Saidi
30 */
31
1/*
2 * Copyright (c) 2003-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;

--- 15 unchanged lines hidden (view full) ---

24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Nathan Binkert
29 * Ali Saidi
30 */
31
32#ifdef __SUNPRO_CC
33#include <stdlib.h>
34#include <math.h>
35#endif
36
37#include <cstdlib>
38#include <cmath>
39
40#include "base/fenv.hh"
32#include "base/fenv.hh"
33#include "base/intmath.hh"
34#include "base/misc.hh"
41#include "base/random.hh"
35#include "base/random.hh"
36#include "sim/serialize.hh"
42
43using namespace std;
44
37
38using namespace std;
39
45uint32_t
46getInt32()
40Random::Random()
47{
41{
48 return mrand48() & 0xffffffff;
42 // default random seed taken from original source
43 init(5489);
49}
50
44}
45
51double
52getDouble()
46Random::Random(uint32_t s)
53{
47{
54 return drand48();
48 init(s);
55}
56
49}
50
57double
58m5round(double r)
51Random::Random(uint32_t init_key[], int key_length)
59{
52{
60#if defined(__sun)
61 double val;
62 int oldrnd = m5_fegetround();
63 m5_fesetround(M5_FE_TONEAREST);
64 val = rint(r);
65 m5_fesetround(oldrnd);
66 return val;
67#else
68 return round(r);
69#endif
53 init(init_key, key_length);
70}
71
54}
55
72int64_t
73getUniform(int64_t min, int64_t max)
56Random::~Random()
74{
57{
75 double r;
76 r = drand48() * (max-min) + min;
58}
77
59
78 return (int64_t)m5round(r);
60// To preserve the uniform random distribution between min and max,
61// and allow all numbers to be represented, we generate a uniform
62// random number to the nearest power of two greater than max. If
63// this number doesn't fall between 0 and max, we try again. Anything
64// else would skew the distribution.
65uint32_t
66Random::genrand(uint32_t max)
67{
68 int log = ceilLog2(max);
69 int shift = (sizeof(uint32_t) * 8 - log);
70 uint32_t random;
71
72 do {
73 random = genrand() >> shift;
74 } while (random > max);
75
76 return random;
79}
80
81uint64_t
77}
78
79uint64_t
82getUniformPos(uint64_t min, uint64_t max)
80Random::genrand(uint64_t max)
83{
81{
84 double r;
85 r = drand48() * (max-min) + min;
82 int log = ceilLog2(max);
83 int shift = (sizeof(uint64_t) * 8 - log);
84 uint64_t random;
86
85
87 return (uint64_t)m5round(r);
86 do {
87 random = (uint64_t)genrand() << 32 | (uint64_t)genrand();
88 random = random >> shift;
89 } while (random > max);
90
91 return random;
88}
92}
93
94void
95Random::serialize(const string &base, ostream &os)
96{
97 int length = N;
98 paramOut(os, base + ".mti", mti);
99 paramOut(os, base + ".length", length);
100 arrayParamOut(os, base + ".data", mt, length);
101}
102
103void
104Random::unserialize(const string &base, Checkpoint *cp, const string &section)
105{
106 int length;
107
108 paramIn(cp, section, base + ".mti", mti);
109 paramIn(cp, section, base + ".length", length);
110 if (length != N)
111 panic("cant unserialize random number data. length != %d\n", length);
112
113 arrayParamIn(cp, section, base + ".data", mt, length);
114}
115
116Random random_mt;