gem5/base/random.cc
Nathan Binkert d0bff50bba Fix up the random number stuff.
SConscript:
    compile the random number generator stuff into m5
base/random.cc:
    we need to define our destructor
base/random.hh:
    Since there's no state, just makes all of these get functions static

--HG--
extra : convert_revision : 9d4b8abd57367391a8ecda3914b1d912d9c64185
2004-12-13 12:55:13 -05:00

79 lines
2.4 KiB
C++

/*
* Copyright (c) 2003 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* 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;
* neither the name of the copyright holders nor the names of its
* contributors may 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.
*/
#include <cstdlib>
#include <cmath>
#include "sim/param.hh"
#include "base/random.hh"
using namespace std;
class RandomContext : public ParamContext
{
public:
RandomContext(const string &_iniSection)
: ::ParamContext(_iniSection) {}
~RandomContext() {}
void checkParams();
};
RandomContext paramContext("random");
Param<unsigned>
seed(&paramContext, "seed", "seed to random number generator", 1);
void
RandomContext::checkParams()
{
::srandom(seed);
}
long
getLong()
{
return random();
}
// idea for generating a double from erand48
double
getDouble()
{
union {
uint32_t _long[2];
uint16_t _short[4];
};
_long[0] = random();
_long[1] = random();
return ldexp((double) _short[0], -48) +
ldexp((double) _short[1], -32) +
ldexp((double) _short[2], -16);
}