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/* Definitions for simple data type for real numbers.
Copyright (C) 2002-2014 Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#ifndef GCC_SREAL_H
#define GCC_SREAL_H
/* SREAL_PART_BITS has to be an even number. */
#define SREAL_PART_BITS 32
#define UINT64_BITS 64
#define SREAL_MIN_SIG ((int64_t) 1 << (SREAL_PART_BITS - 2))
#define SREAL_MAX_SIG (((int64_t) 1 << (SREAL_PART_BITS - 1)) - 1)
#define SREAL_MAX_EXP (INT_MAX / 4)
#define SREAL_BITS SREAL_PART_BITS
/* Structure for holding a simple real number. */
class sreal
{
public:
/* Construct an uninitialized sreal. */
sreal () : m_sig (-1), m_exp (-1) {}
/* Construct a sreal. */
sreal (int64_t sig, int exp = 0) : m_sig (sig), m_exp (exp)
{
normalize ();
}
void dump (FILE *) const;
int64_t to_int () const;
sreal operator+ (const sreal &other) const;
sreal operator- (const sreal &other) const;
sreal operator* (const sreal &other) const;
sreal operator/ (const sreal &other) const;
bool operator< (const sreal &other) const
{
if (m_exp == other.m_exp)
return m_sig < other.m_sig;
else
{
bool negative = m_sig < 0;
bool other_negative = other.m_sig < 0;
if (negative != other_negative)
return negative > other_negative;
bool r = m_exp < other.m_exp;
return negative ? !r : r;
}
}
bool operator== (const sreal &other) const
{
return m_exp == other.m_exp && m_sig == other.m_sig;
}
sreal operator- () const
{
sreal tmp = *this;
tmp.m_sig *= -1;
return tmp;
}
sreal shift (int s) const
{
gcc_checking_assert (s <= SREAL_BITS);
gcc_checking_assert (s >= -SREAL_BITS);
/* Exponent should never be so large because shift_right is used only by
sreal_add and sreal_sub ant thus the number cannot be shifted out from
exponent range. */
gcc_checking_assert (m_exp + s <= SREAL_MAX_EXP);
gcc_checking_assert (m_exp + s >= -SREAL_MAX_EXP);
sreal tmp = *this;
tmp.m_exp += s;
return tmp;
}
/* Global minimum sreal can hold. */
inline static sreal min ()
{
static sreal min = sreal (-SREAL_MAX_SIG, SREAL_MAX_EXP);
return min;
}
/* Global minimum sreal can hold. */
inline static sreal max ()
{
static sreal max = sreal (SREAL_MAX_SIG, SREAL_MAX_EXP);
return max;
}
private:
void normalize ();
void shift_right (int amount);
static sreal signedless_plus (const sreal &a, const sreal &b, bool negative);
static sreal signedless_minus (const sreal &a, const sreal &b, bool negative);
int64_t m_sig; /* Significant. */
signed int m_exp; /* Exponent. */
};
extern void debug (const sreal &ref);
extern void debug (const sreal *ptr);
inline sreal &operator+= (sreal &a, const sreal &b)
{
return a = a + b;
}
inline sreal &operator-= (sreal &a, const sreal &b)
{
return a = a - b;
}
inline sreal &operator/= (sreal &a, const sreal &b)
{
return a = a / b;
}
inline sreal &operator*= (sreal &a, const sreal &b)
{
return a = a * b;
}
inline bool operator!= (const sreal &a, const sreal &b)
{
return !(a == b);
}
inline bool operator> (const sreal &a, const sreal &b)
{
return !(a == b || a < b);
}
inline bool operator<= (const sreal &a, const sreal &b)
{
return a < b || a == b;
}
inline bool operator>= (const sreal &a, const sreal &b)
{
return a == b || a > b;
}
inline sreal operator<< (const sreal &a, int exp)
{
return a.shift (exp);
}
inline sreal operator>> (const sreal &a, int exp)
{
return a.shift (-exp);
}
#endif
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