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 #if defined(__sun)
  33 #include <ieeefp.h>
  34 #endif
  35 #ifdef __SUNPRO_CC
  36 #include <stdlib.h>
  37 #include <math.h>
  38 #endif
  39
  40 #include <cstdlib>
  41 #include <cmath>
  42
  43 #include "base/random.hh"
  44
  45 using namespace std;
  46
  47 uint32_t
  48 getInt32()
  49 {
  50     return mrand48() & 0xffffffff;
  51 }
  52
  53 double
  54 getDouble()
  55 {
  56     return drand48();
  57 }
  58
  59 double
  60 m5round(double r)
  61 {
  62 #if defined(__sun)
  63     double val;
  64     fp_rnd oldrnd = fpsetround(FP_RN);
  65     val = rint(r);
  66     fpsetround(oldrnd);
  67     return val;
  68 #else
  69     return round(r);
  70 #endif
  71 }
  72
  73 int64_t
  74 getUniform(int64_t min, int64_t max)
  75 {
  76     double r;
  77     r = drand48() * (max-min) + min;
  78
  79     return (int64_t)m5round(r);
  80 }
  81
  82 uint64_t
  83 getUniformPos(uint64_t min, uint64_t max)
  84 {
  85     double r;
  86     r = drand48() * (max-min) + min;
  87
  88     return (uint64_t)m5round(r);
  89 }