random.cc revision 10905 
1/*
2 * Copyright (c) 2014 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2003-2005 The Regents of The University of Michigan
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Nathan Binkert
41 *          Ali Saidi
42 *          Andreas Hansson
43 */
44
45#include <sstream>
46
47#include "base/misc.hh"
48#include "base/random.hh"
49#include "sim/serialize.hh"
50
51Random::Random()
52{
53    // default random seed
54    init(5489);
55}
56
57Random::Random(uint32_t s)
58{
59    init(s);
60}
61
62Random::~Random()
63{
64}
65
66void
67Random::init(uint32_t s)
68{
69    gen.seed(s);
70}
71
72void
73Random::serialize(CheckpointOut &cp) const
74{
75    panic("Currently not used anywhere.\n");
76
77    // get the state from the generator
78    std::ostringstream oss;
79    oss << gen;
80    std::string state = oss.str();
81    paramOut(cp, "mt_state", state);
82}
83
84void
85Random::unserialize(CheckpointIn &cp)
86{
87    panic("Currently not used anywhere.\n");
88
89    // the random generator state did not use to be part of the
90    // checkpoint state, so be forgiving in the unserialization and
91    // keep on going if the parameter is not there
92    std::string state;
93    if (optParamIn(cp, "mt_state", state)) {
94        std::istringstream iss(state);
95        iss >> gen;
96    }
97}
98
99Random random_mt;
100