gcc/sreal.h

   1 /* Definitions for simple data type for positive real numbers.
   2    Copyright (C) 2002-2014 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_SREAL_H
  21 #define GCC_SREAL_H
  22
  23 /* SREAL_PART_BITS has to be an even number.  */
  24 #define SREAL_PART_BITS 32
  25
  26 #define SREAL_MIN_SIG ((uint64_t) 1 << (SREAL_PART_BITS - 1))
  27 #define SREAL_MAX_SIG (((uint64_t) 1 << SREAL_PART_BITS) - 1)
  28 #define SREAL_MAX_EXP (INT_MAX / 4)
  29
  30 #define SREAL_BITS SREAL_PART_BITS
  31
  32 /* Structure for holding a simple real number.  */
  33 class sreal
  34 {
  35 public:
  36   /* Construct an uninitialized sreal.  */
  37   sreal () : m_sig (-1), m_exp (-1) {}
  38
  39   /* Construct a sreal.  */
  40   sreal (uint64_t sig, int exp) : m_sig (sig), m_exp (exp) { normalize (); }
  41
  42   void dump (FILE *) const;
  43   int64_t to_int () const;
  44
  45   sreal operator+ (const sreal &other) const;
  46   sreal operator- (const sreal &other) const;
  47   sreal operator* (const sreal &other) const;
  48   sreal operator/ (const sreal &other) const;
  49
  50   bool operator< (const sreal &other) const
  51   {
  52     return m_exp < other.m_exp
  53       || (m_exp == other.m_exp && m_sig < other.m_sig);
  54   }
  55
  56   bool operator== (const sreal &other) const
  57   {
  58     return m_exp == other.m_exp && m_sig == other.m_sig;
  59   }
  60
  61 private:
  62   void normalize ();
  63   void shift_right (int amount);
  64
  65   uint64_t m_sig;               /* Significant.  */
  66   signed int m_exp;                     /* Exponent.  */
  67 };
  68
  69 extern void debug (sreal &ref);
  70 extern void debug (sreal *ptr);
  71
  72 inline sreal &operator+= (sreal &a, const sreal &b)
  73 {
  74   return a = a + b;
  75 }
  76
  77 inline sreal &operator-= (sreal &a, const sreal &b)
  78 {
  79 return a = a - b;
  80 }
  81
  82 inline sreal &operator/= (sreal &a, const sreal &b)
  83 {
  84 return a = a / b;
  85 }
  86
  87 inline sreal &operator*= (sreal &a, const sreal &b)
  88 {
  89   return a = a  * b;
  90 }
  91
  92 inline bool operator!= (const sreal &a, const sreal &b)
  93 {
  94   return !(a == b);
  95 }
  96
  97 inline bool operator> (const sreal &a, const sreal &b)
  98 {
  99   return !(a == b || a < b);
 100 }
 101
 102 inline bool operator<= (const sreal &a, const sreal &b)
 103 {
 104   return a < b || a == b;
 105 }
 106
 107 inline bool operator>= (const sreal &a, const sreal &b)
 108 {
 109   return a == b || a > b;
 110 }
 111
 112 #endif