src/base/random.cc

   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;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  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/random.hh"
  41
  42 using namespace std;
  43
  44 uint32_t
  45 getInt32()
  46 {
  47     return mrand48() & 0xffffffff;
  48 }
  49
  50 double
  51 getDouble()
  52 {
  53     return drand48();
  54 }
  55
  56 double
  57 m5round(double r)
  58 {
  59 #if defined(__sun)
  60     double val;
  61     int oldrnd = m5_fegetround();
  62     m5_fesetround(M5_FP_TONEAREST);
  63     val = rint(r);
  64     m5_fesetround(oldrnd);
  65     return val;
  66 #else
  67     return round(r);
  68 #endif
  69 }
  70
  71 int64_t
  72 getUniform(int64_t min, int64_t max)
  73 {
  74     double r;
  75     r = drand48() * (max-min) + min;
  76
  77     return (int64_t)m5round(r);
  78 }
  79
  80 uint64_t
  81 getUniformPos(uint64_t min, uint64_t max)
  82 {
  83     double r;
  84     r = drand48() * (max-min) + min;
  85
  86     return (uint64_t)m5round(r);
  87 }