random.cc revision 1971
12292SN/A/* 22292SN/A * Copyright (c) 2003-2005 The Regents of The University of Michigan 32292SN/A * All rights reserved. 42292SN/A * 52292SN/A * Redistribution and use in source and binary forms, with or without 62292SN/A * modification, are permitted provided that the following conditions are 72292SN/A * met: redistributions of source code must retain the above copyright 82292SN/A * notice, this list of conditions and the following disclaimer; 92292SN/A * redistributions in binary form must reproduce the above copyright 102292SN/A * notice, this list of conditions and the following disclaimer in the 112292SN/A * documentation and/or other materials provided with the distribution; 122292SN/A * neither the name of the copyright holders nor the names of its 132292SN/A * contributors may be used to endorse or promote products derived from 142292SN/A * this software without specific prior written permission. 152292SN/A * 162292SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 172292SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 182292SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 192292SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 202292SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 212292SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 222292SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 232292SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 242292SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 252292SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 262292SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 272689Sktlim@umich.edu */ 282689Sktlim@umich.edu 292689Sktlim@umich.edu#include <cstdlib> 302292SN/A#include <cmath> 312292SN/A 322316SN/A#include "sim/param.hh" 332292SN/A#include "base/random.hh" 342292SN/A#include "base/trace.hh" 352669Sktlim@umich.edu 362292SN/Ausing namespace std; 372669Sktlim@umich.edu 382678Sktlim@umich.educlass RandomContext : public ParamContext 392678Sktlim@umich.edu{ 402678Sktlim@umich.edu public: 412292SN/A RandomContext(const string &_iniSection) 422678Sktlim@umich.edu : ::ParamContext(_iniSection) {} 432292SN/A ~RandomContext() {} 442292SN/A 452669Sktlim@umich.edu void checkParams(); 462292SN/A}; 472678Sktlim@umich.edu 482292SN/ARandomContext paramContext("random"); 492678Sktlim@umich.edu 502678Sktlim@umich.eduParam<unsigned> 512678Sktlim@umich.eduseed(¶mContext, "seed", "seed to random number generator", 1); 522678Sktlim@umich.edu 532678Sktlim@umich.eduvoid 542292SN/ARandomContext::checkParams() 552678Sktlim@umich.edu{ 562678Sktlim@umich.edu ::srand48(seed); 572678Sktlim@umich.edu} 582678Sktlim@umich.edu 592678Sktlim@umich.edulong 602678Sktlim@umich.edugetLong() 612292SN/A{ 622678Sktlim@umich.edu return mrand48(); 632678Sktlim@umich.edu} 642678Sktlim@umich.edu 652678Sktlim@umich.eduint64_t 662678Sktlim@umich.edugetUniform(int64_t min, int64_t max) 672678Sktlim@umich.edu{ 682678Sktlim@umich.edu double r; 692698Sktlim@umich.edu r = drand48() * (max-min) + min; 702344SN/A return (int64_t)round(r); 712678Sktlim@umich.edu} 722678Sktlim@umich.edu 732678Sktlim@umich.eduuint64_t 742678Sktlim@umich.edugetUniformPos(uint64_t min, uint64_t max) 752678Sktlim@umich.edu{ 762307SN/A double r; 772678Sktlim@umich.edu r = drand48() * (max-min) + min; 782678Sktlim@umich.edu return (uint64_t)round(r); 792678Sktlim@umich.edu} 802678Sktlim@umich.edu 812678Sktlim@umich.edu 822678Sktlim@umich.edu// idea for generating a double from erand48 832678Sktlim@umich.edudouble 842678Sktlim@umich.edugetDouble() 852344SN/A{ 862307SN/A union { 872678Sktlim@umich.edu uint32_t _long[2]; 882678Sktlim@umich.edu uint16_t _short[4]; 892292SN/A }; 902292SN/A 912292SN/A _long[0] = mrand48(); 922669Sktlim@umich.edu _long[1] = mrand48(); 932669Sktlim@umich.edu 942292SN/A return ldexp((double) _short[0], -48) + 952669Sktlim@umich.edu ldexp((double) _short[1], -32) + 962669Sktlim@umich.edu ldexp((double) _short[2], -16); 972669Sktlim@umich.edu} 982669Sktlim@umich.edu