freebsd-dev/gnu/lib/libg++/include/Fix.h

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// -*- C++ -*-
// Fix.h : variable length fixed point data type
//
#ifndef _Fix_h
#ifdef __GNUG__
#pragma interface
#endif
#define _Fix_h 1
#include <stream.h>
#include <std.h>
#include <stddef.h>
#include <Integer.h>
#include <builtin.h>
class Fix
{
struct Rep // internal Fix representation
{
_G_uint16_t len; // length in bits
_G_uint16_t siz; // allocated storage
_G_int16_t ref; // reference count
_G_uint16_t s[1]; // start of ushort array represention
};
public:
typedef void (*PEH)(Rep*);
private:
Rep* rep;
Fix(Rep*);
Fix(int, const Rep*);
void unique();
static const _G_uint16_t min_length = 1;
static const _G_uint16_t max_length = 65535;
static const double min_value = -1.0;
static const double max_value = 1.0;
static _G_uint16_t default_length;
static int default_print_width;
static Rep Rep_0;
static Rep Rep_m1;
static Rep Rep_quotient_bump;
// internal class functions
static void mask(Rep*);
static int compare(const Rep*, const Rep* = &Rep_0);
static Rep* new_Fix(_G_uint16_t);
static Rep* new_Fix(_G_uint16_t, const Rep*);
static Rep* new_Fix(_G_uint16_t, double);
static Rep* copy(const Rep*, Rep*);
static Rep* negate(const Rep*, Rep* = NULL);
static Rep* add(const Rep*, const Rep*, Rep* = NULL);
static Rep* subtract(const Rep*, const Rep*, Rep* = NULL);
static Rep* multiply(const Rep*, const Rep*, Rep* = NULL);
static Rep* multiply(const Rep*, int, Rep* = NULL);
static Rep* divide(const Rep*, const Rep*, Rep* = NULL,
Rep* = NULL);
static Rep* shift(const Rep*, int, Rep* = NULL);
static one_arg_error_handler_t error_handler;
static one_arg_error_handler_t range_error_handler;
static PEH overflow_handler;
public:
Fix();
Fix(const Fix&);
Fix(double);
Fix(int);
Fix(int, const Fix&);
Fix(int, double);
~Fix();
Fix operator = (const Fix&);
Fix operator = (double);
friend int operator == (const Fix&, const Fix&);
friend int operator != (const Fix&, const Fix&);
friend int operator < (const Fix&, const Fix&);
friend int operator <= (const Fix&, const Fix&);
friend int operator > (const Fix&, const Fix&);
friend int operator >= (const Fix&, const Fix&);
Fix& operator + ();
Fix operator - ();
friend Fix operator + (const Fix&, const Fix&);
friend Fix operator - (const Fix&, const Fix&);
friend Fix operator * (const Fix&, const Fix&);
friend Fix operator / (const Fix&, const Fix&);
friend Fix operator * (const Fix&, int);
friend Fix operator * (int, const Fix&);
friend Fix operator % (const Fix&, int);
friend Fix operator << (const Fix&, int);
friend Fix operator >> (const Fix&, int);
#if defined (__GNUG__) && ! defined (__STRICT_ANSI__)
friend Fix operator <? (const Fix&, const Fix&); // min
friend Fix operator >? (const Fix&, const Fix&); // max
#endif
Fix operator += (const Fix&);
Fix operator -= (const Fix&);
Fix operator *= (const Fix&);
Fix operator /= (const Fix&);
Fix operator *= (int);
Fix operator %= (int);
Fix operator <<=(int);
Fix operator >>=(int);
friend char* Ftoa(const Fix&, int width = default_print_width);
void printon(ostream&, int width = default_print_width) const;
friend Fix atoF(const char*, int len = default_length);
friend istream& operator >> (istream&, Fix&);
friend ostream& operator << (ostream&, const Fix&);
// built-in functions
friend Fix abs(Fix); // absolute value
friend int sgn(const Fix&); // -1, 0, +1
friend Integer mantissa(const Fix&); // integer representation
friend double value(const Fix&); // double value
friend int length(const Fix&); // field length
friend void show(const Fix&); // show contents
// error handlers
static void error(const char* msg); // error handler
static void range_error(const char* msg); // range error handler
static one_arg_error_handler_t set_error_handler(one_arg_error_handler_t f);
static one_arg_error_handler_t
set_range_error_handler(one_arg_error_handler_t f);
static void default_error_handler (const char *);
static void default_range_error_handler (const char *);
// non-operator versions for user
friend void negate(const Fix& x, Fix& r);
friend void add(const Fix& x, const Fix& y, Fix& r);
friend void subtract(const Fix& x, const Fix& y, Fix& r);
friend void multiply(const Fix& x, const Fix& y, Fix& r);
friend void divide(const Fix& x, const Fix& y, Fix& q, Fix& r);
friend void shift(const Fix& x, int y, Fix& r);
// overflow handlers
static void overflow_saturate(Fix::Rep*);
static void overflow_wrap(Fix::Rep*);
static void overflow_warning_saturate(Fix::Rep*);
static void overflow_warning(Fix::Rep*);
static void overflow_error(Fix::Rep*);
static PEH set_overflow_handler(PEH);
static int set_default_length(int);
};
// function definitions
inline void
Fix::unique()
{
if ( rep->ref > 1 )
{
rep->ref--;
rep = new_Fix(rep->len,rep);
}
}
inline void
Fix::mask (Fix::Rep* x)
{
int n = x->len & 0x0f;
if ( n )
x->s[x->siz - 1] &= 0xffff0000 >> n;
}
inline Fix::Rep*
Fix::copy(const Fix::Rep* from, Fix::Rep* to)
{
_G_uint16_t *ts = to->s;
const _G_uint16_t *fs = from->s;
int ilim = to->siz < from->siz ? to->siz : from->siz;
for ( int i=0; i < ilim; i++ )
*ts++ = *fs++;
for ( ; i < to->siz; i++ )
*ts++ = 0;
mask(to);
return to;
}
inline
Fix::Fix(Rep* f)
{
rep = f;
}
inline
Fix::Fix()
{
rep = new_Fix(default_length);
}
inline
Fix::Fix(int len)
{
if ( len < min_length || len > max_length )
error("illegal length in declaration");
rep = new_Fix((_G_uint16_t) len);
}
inline
Fix::Fix(double d)
{
rep = new_Fix(default_length,d);
}
inline
Fix::Fix(const Fix& y)
{
rep = y.rep; rep->ref++;
}
inline
Fix::Fix(int len, const Fix& y)
{
if ( len < Fix::min_length || len > Fix::max_length )
error("illegal length in declaration");
rep = new_Fix((_G_uint16_t) len,y.rep);
}
inline
Fix::Fix(int len, const Rep* fr)
{
if ( len < Fix::min_length || len > Fix::max_length )
error("illegal length in declaration");
rep = new_Fix((_G_uint16_t) len,fr);
}
inline
Fix::Fix(int len, double d)
{
if ( len < Fix::min_length || len > Fix::max_length )
error("illegal length in declaration");
rep = new_Fix((_G_uint16_t) len,d);
}
inline
Fix::~Fix()
{
if ( --rep->ref <= 0 ) delete rep;
}
inline Fix
Fix::operator = (const Fix& y)
{
if ( rep->len == y.rep->len ) {
++y.rep->ref;
if ( --rep->ref <= 0 ) delete rep;
rep = y.rep;
}
else {
unique();
copy(y.rep,rep);
}
return *this;
}
inline Fix
Fix::operator = (double d)
{
int oldlen = rep->len;
if ( --rep->ref <= 0 ) delete rep;
rep = new_Fix(oldlen,d);
return *this;
}
inline int
operator == (const Fix& x, const Fix& y)
{
return Fix::compare(x.rep, y.rep) == 0;
}
inline int
operator != (const Fix& x, const Fix& y)
{
return Fix::compare(x.rep, y.rep) != 0;
}
inline int
operator < (const Fix& x, const Fix& y)
{
return Fix::compare(x.rep, y.rep) < 0;
}
inline int
operator <= (const Fix& x, const Fix& y)
{
return Fix::compare(x.rep, y.rep) <= 0;
}
inline int
operator > (const Fix& x, const Fix& y)
{
return Fix::compare(x.rep, y.rep) > 0;
}
inline int
operator >= (const Fix& x, const Fix& y)
{
return Fix::compare(x.rep, y.rep) >= 0;
}
inline Fix&
Fix::operator + ()
{
return *this;
}
inline Fix
Fix::operator - ()
{
Rep* r = negate(rep); return r;
}
inline Fix
operator + (const Fix& x, const Fix& y)
{
Fix::Rep* r = Fix::add(x.rep, y.rep); return r;
}
inline Fix
operator - (const Fix& x, const Fix& y)
{
Fix::Rep* r = Fix::subtract(x.rep, y.rep); return r;
}
inline Fix
operator * (const Fix& x, const Fix& y)
{
Fix::Rep* r = Fix::multiply(x.rep, y.rep); return r;
}
inline Fix
operator * (const Fix& x, int y)
{
Fix::Rep* r = Fix::multiply(x.rep, y); return r;
}
inline Fix
operator * (int y, const Fix& x)
{
Fix::Rep* r = Fix::multiply(x.rep, y); return r;
}
inline Fix
operator / (const Fix& x, const Fix& y)
{
Fix::Rep* r = Fix::divide(x.rep, y.rep); return r;
}
inline Fix
Fix::operator += (const Fix& y)
{
unique(); Fix::add(rep, y.rep, rep); return *this;
}
inline Fix
Fix::operator -= (const Fix& y)
{
unique(); Fix::subtract(rep, y.rep, rep); return *this;
}
inline Fix
Fix::operator *= (const Fix& y)
{
unique(); Fix::multiply(rep, y.rep, rep); return *this;
}
inline Fix
Fix::operator *= (int y)
{
unique(); Fix::multiply(rep, y, rep); return *this;
}
inline Fix
Fix::operator /= (const Fix& y)
{
unique(); Fix::divide(rep, y.rep, rep); return *this;
}
inline Fix
operator % (const Fix& x, int y)
{
Fix r((int) x.rep->len + y, x); return r;
}
inline Fix
operator << (const Fix& x, int y)
{
Fix::Rep* rep = Fix::shift(x.rep, y); return rep;
}
inline Fix
operator >> (const Fix& x, int y)
{
Fix::Rep* rep = Fix::shift(x.rep, -y); return rep;
}
inline Fix
Fix::operator <<= (int y)
{
unique(); Fix::shift(rep, y, rep); return *this;
}
inline Fix
Fix::operator >>= (int y)
{
unique(); Fix::shift(rep, -y, rep); return *this;
}
#if defined (__GNUG__) && ! defined (__STRICT_ANSI__)
inline Fix
operator <? (const Fix& x, const Fix& y)
{
if ( Fix::compare(x.rep, y.rep) <= 0 ) return x; else return y;
}
inline Fix
operator >? (const Fix& x, const Fix& y)
{
if ( Fix::compare(x.rep, y.rep) >= 0 ) return x; else return y;
}
#endif
inline Fix
abs(Fix x)
{
Fix::Rep* r = (Fix::compare(x.rep) >= 0 ? Fix::new_Fix(x.rep->len,x.rep) :
Fix::negate(x.rep));
return r;
}
inline int
sgn(const Fix& x)
{
int a = Fix::compare(x.rep);
return a == 0 ? 0 : (a > 0 ? 1 : -1);
}
inline int
length(const Fix& x)
{
return x.rep->len;
}
inline ostream&
operator << (ostream& s, const Fix& y)
{
if (s.opfx())
y.printon(s);
return s;
}
inline void
negate (const Fix& x, Fix& r)
{
Fix::negate(x.rep, r.rep);
}
inline void
add (const Fix& x, const Fix& y, Fix& r)
{
Fix::add(x.rep, y.rep, r.rep);
}
inline void
subtract (const Fix& x, const Fix& y, Fix& r)
{
Fix::subtract(x.rep, y.rep, r.rep);
}
inline void
multiply (const Fix& x, const Fix& y, Fix& r)
{
Fix::multiply(x.rep, y.rep, r.rep);
}
inline void
divide (const Fix& x, const Fix& y, Fix& q, Fix& r)
{
Fix::divide(x.rep, y.rep, q.rep, r.rep);
}
inline void
shift (const Fix& x, int y, Fix& r)
{
Fix::shift(x.rep, y, r.rep);
}
#endif