values.h

早期freebsd实现

// This may look like C code, but it is really -*- C++ -*-
/* 
Copyright (C) 1988 Free Software Foundation
    written by Doug Lea ([e-mail])

This file is part of the GNU C++ Library.  This library is free
software; you can redistribute it and/or modify it under the terms of
the GNU Library General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version.  This library 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 Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/


#ifndef _values_h
#define _values_h 1

#define BITSPERBYTE 8
#define BITS(type)  (BITSPERBYTE * (int)sizeof(type))

#define CHARBITS    BITS(char)
#define SHORTBITS   BITS(short)
#define INTBITS     BITS(int)
#define LONGBITS    BITS(long)
#define PTRBITS     BITS(char*)
#define DOUBLEBITS  BITS(double)
#define FLOATBITS   BITS(float)

#define MINSHORT    ((short)(1 << (SHORTBITS - 1)))
#define MININT      (1 << (INTBITS - 1))
#define MINLONG     (1L << (LONGBITS - 1))

#define MAXSHORT    ((short)~MINSHORT)
#define MAXINT      (~MININT)
#define MAXLONG     (~MINLONG)

#define HIBITS	MINSHORT
#define HIBITL	MINLONG

#if defined(sun) || defined(hp300) || defined(hpux) || defined(masscomp) || defined(sgi)
#ifdef masscomp
#define MAXDOUBLE							\
({									\
  double maxdouble_val;							\
									\
  __asm ("fmove%.d #0x7fefffffffffffff,%0"	/* Max double */	\
	 : "=f" (maxdouble_val)						\
	 : /* no inputs */);						\
  maxdouble_val;							\
})
#define MAXFLOAT ((float) 3.40e+38)
#else
#define MAXDOUBLE   1.79769313486231470e+308
#define MAXFLOAT    ((float)3.40282346638528860e+38)
#endif
#define MINDOUBLE   4.94065645841246544e-324
#define MINFLOAT    ((float)1.40129846432481707e-45)
#define _IEEE       1
#define _DEXPLEN    11
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (-(DMAXEXP + DSIGNIF - _HIDDENBIT - 3))
#define FMINEXP     (-(FMAXEXP + FSIGNIF - _HIDDENBIT - 3))
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)

#elif defined(sony) 
#define MAXDOUBLE   1.79769313486231470e+308
#define MAXFLOAT    ((float)3.40282346638528860e+38)
#define MINDOUBLE   2.2250738585072010e-308
#define MINFLOAT    ((float)1.17549435e-38)
#define _IEEE       1
#define _DEXPLEN    11
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (-(DMAXEXP + DSIGNIF - _HIDDENBIT - 3))
#define FMINEXP     (-(FMAXEXP + FSIGNIF - _HIDDENBIT - 3))
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)

#elif defined(sequent)
extern double _maxdouble, _mindouble;
extern float _maxfloat, _minfloat;
#define MAXDOUBLE	_maxdouble
#define MAXFLOAT	_maxfloat
#define MINDOUBLE	_mindouble
#define MINFLOAT	_minfloat
#define _IEEE       1
#define _DEXPLEN    11
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (-(DMAXEXP - 3))
#define FMINEXP     (-(FMAXEXP - 3))
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)

#elif defined(i386)
#define MAXDOUBLE   1.79769313486231570e+308
#define MAXFLOAT    ((float)3.40282346638528860e+38)
#define MINDOUBLE   2.22507385850720140e-308
#define MINFLOAT    ((float)1.17549435082228750e-38)
#define _IEEE       0
#define _DEXPLEN    11
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (-DMAXEXP)
#define FMINEXP     (-FMAXEXP)
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)

/* from Andrew Klossner <[e-mail]> */
#elif defined(m88k)
	/* These are "good" guesses ...
	   I'll figure out the true mins and maxes later, at the time I find
	   out the mins and maxes that the compiler can tokenize. */
#define MAXDOUBLE   1.79769313486231e+308
#define MAXFLOAT    ((float)3.40282346638528e+38)
#define MINDOUBLE   2.22507385850720e-308
#define MINFLOAT    ((float)1.17549435082228e-38)
#define _IEEE       1
#define _DEXPLEN    11
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (1-DMAXEXP)
#define FMINEXP     (1-FMAXEXP)
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)

#elif defined(convex)
#define MAXDOUBLE   8.9884656743115785e+306
#define MAXFLOAT    ((float) 1.70141173e+38)
#define MINDOUBLE   5.5626846462680035e-308
#define MINFLOAT    ((float) 2.93873588e-39)
#define _IEEE       0
#define _DEXPLEN    11
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (-DMAXEXP)
#define FMINEXP     (-FMAXEXP)
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)

// #elif defined(vax)
// use vax versions by default -- they seem to be the most conservative
#else 

#define MAXDOUBLE   1.701411834604692293e+38
#define MINDOUBLE   (2.938735877055718770e-39)

#define MAXFLOAT    1.7014117331926443e+38
#define MINFLOAT    2.9387358770557188e-39

#define _IEEE       0
#define _DEXPLEN    8
#define _FEXPLEN    8
#define _HIDDENBIT  1
#define DMINEXP     (-DMAXEXP)
#define FMINEXP     (-FMAXEXP)
#define DMAXEXP     ((1 << _DEXPLEN - 1) - 1 + _IEEE)
#define FMAXEXP     ((1 << _FEXPLEN - 1) - 1 + _IEEE)
#endif

#define DSIGNIF     (DOUBLEBITS - _DEXPLEN + _HIDDENBIT - 1)
#define FSIGNIF     (FLOATBITS  - _FEXPLEN + _HIDDENBIT - 1)
#define DMAXPOWTWO  ((double)(1L << LONGBITS -2)*(1L << DSIGNIF - LONGBITS +1))
#define FMAXPOWTWO  ((float)(1L << FSIGNIF - 1))

#endif