1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

     2 /*

     3  * Copyright (c) 2006 INRIA

     4  * All rights reserved.

     5  *

     6  * This program is free software; you can redistribute it and/or modify

     7  * it under the terms of the GNU General Public License version 2 as

     8  * published by the Free Software Foundation;

     9  *

    10  * This program is distributed in the hope that it will be useful,

    11  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    13  * GNU General Public License for more details.

    14  *

    15  * You should have received a copy of the GNU General Public License

    16  * along with this program; if not, write to the Free Software

    17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    18  *

    19  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

    20  */

    21 #ifndef HIGH_PRECISION_H

    22 #define HIGH_PRECISION_H

    23 

    24 #include <stdint.h>

    25 

    26 #ifdef HIGH_PRECISION_I128

    27 

    28 /**

    29  * This should be a high-precision 128bit integer version of

    30  * HighPrecision class. It should also be able to report 

    31  * overflow and underflow.

    32  */

    33 class HighPrecision 

    34 {

    35 public:

    36   HighPrecision ();

    37   HighPrecision (int64_t high, int64_t low);

    38   HighPrecision (double value);

    39   

    40   int64_t GetHigh (void) const;

    41   int64_t GetLow (void) const;

    42   double GetDouble (void) const;

    43   bool Add (HighPrecision const &o);

    44   bool Sub (HighPrecision const &o);

    45   bool Mul (HighPrecision const &o);

    46   bool Div (HighPrecision const &o);

    47 

    48   int Compare (HighPrecision const &o) const;

    49   static HighPrecision Zero (void);

    50 private:

    51   int64_t m_high;

    52   int64_t m_low;

    53 };

    54 

    55 

    56 #else /* HIGH_PRECISION_I128 */

    57 

    58 /**

    59  * Obviously, this implementation of the HighPrecision class does

    60  * not provide the 128 bits accuracy since it uses a an IEEE754 double

    61  * to store the value. It also does not report overflows.

    62  * So, it is a nice shortcut but in no way a complete solution.

    63  */

    64 

    65 class HighPrecision 

    66 {

    67 public:

    68   HighPrecision ();

    69   HighPrecision (int64_t high, int64_t low);

    70   HighPrecision (double value);

    71   

    72   int64_t GetHigh (void) const;

    73   int64_t GetLow (void) const;

    74   double GetDouble (void) const;

    75   bool Add (HighPrecision const &o);

    76   bool Sub (HighPrecision const &o);

    77   bool Mul (HighPrecision const &o);

    78   bool Div (HighPrecision const &o);

    79 

    80   int Compare (HighPrecision const &o) const;

    81   static HighPrecision Zero (void);

    82 private:

    83   static const double MAX_64;

    84   double m_value;

    85 };

    86 

    87 #endif /* HIGH_PRECISION_I128 */

    88 

    89 

    90 

    91 #endif /* HIGH_PRECISION_H */