float.h

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

/*
 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
 *
 * Floating-point emulation code
 *  Copyright (C) 2001 Hewlett-Packard (Paul Bame) <[e-mail]>
 *
 *    This program 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 2, or (at your option)
 *    any later version.
 *
 *    This program 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 this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
/*
 * BEGIN_DESC
 * 
 *  File: 
 *      @(#)	pa/spmath/float.h		$Revision: 1.2 $
 * 
 *  Purpose:
 *      <<please update with a synopis of the functionality provided by this file>>
 * 
 *  BE header:  no
 *
 *  Shipped:  yes
 *	/usr/conf/pa/spmath/float.h
 *
 * END_DESC  
*/

#ifdef __NO_PA_HDRS
    PA header file -- do not include this header file for non-PA builds.
#endif

#include "fpbits.h"
#include "hppa.h"
/*
 * Want to pick up the FPU capability flags, not the PDC structures.
 * 'LOCORE' isn't really true in this case, but we don't want the C structures
 * so it suits our purposes
 */
#define LOCORE
#include "fpu.h"

/*
 * Declare the basic structures for the 3 different
 * floating-point precisions.
 *        
 * Single number  
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |s|       exp     |               mantissa                      |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 */
#define	Sall(object) (object)
#define	Ssign(object) Bitfield_extract( 0,  1,object)
#define	Ssignedsign(object) Bitfield_signed_extract( 0,  1,object)
#define	Sexponent(object) Bitfield_extract( 1,  8,object)
#define	Smantissa(object) Bitfield_mask( 9, 23,object)
#define	Ssignaling(object) Bitfield_extract( 9,  1,object)
#define	Ssignalingnan(object) Bitfield_extract( 1,  9,object)
#define	Shigh2mantissa(object) Bitfield_extract( 9,  2,object)
#define	Sexponentmantissa(object) Bitfield_mask( 1, 31,object)
#define	Ssignexponent(object) Bitfield_extract( 0,  9,object)
#define	Shidden(object) Bitfield_extract( 8,  1,object)
#define	Shiddenoverflow(object) Bitfield_extract( 7,  1,object)
#define	Shiddenhigh7mantissa(object) Bitfield_extract( 8,  8,object)
#define	Shiddenhigh3mantissa(object) Bitfield_extract( 8,  4,object)
#define	Slow(object) Bitfield_mask( 31,  1,object)
#define	Slow4(object) Bitfield_mask( 28,  4,object)
#define	Slow31(object) Bitfield_mask( 1, 31,object)
#define	Shigh31(object) Bitfield_extract( 0, 31,object)
#define	Ssignedhigh31(object) Bitfield_signed_extract( 0, 31,object)
#define	Shigh4(object) Bitfield_extract( 0,  4,object)
#define	Sbit24(object) Bitfield_extract( 24,  1,object)
#define	Sbit28(object) Bitfield_extract( 28,  1,object)
#define	Sbit29(object) Bitfield_extract( 29,  1,object)
#define	Sbit30(object) Bitfield_extract( 30,  1,object)
#define	Sbit31(object) Bitfield_mask( 31,  1,object)

#define Deposit_ssign(object,value) Bitfield_deposit(value,0,1,object)
#define Deposit_sexponent(object,value) Bitfield_deposit(value,1,8,object)
#define Deposit_smantissa(object,value) Bitfield_deposit(value,9,23,object)
#define Deposit_shigh2mantissa(object,value) Bitfield_deposit(value,9,2,object)
#define Deposit_sexponentmantissa(object,value) \
    Bitfield_deposit(value,1,31,object)
#define Deposit_ssignexponent(object,value) Bitfield_deposit(value,0,9,object)
#define Deposit_slow(object,value) Bitfield_deposit(value,31,1,object)
#define Deposit_shigh4(object,value) Bitfield_deposit(value,0,4,object)

#define	Is_ssign(object) Bitfield_mask( 0,  1,object)
#define	Is_ssignaling(object) Bitfield_mask( 9,  1,object)
#define	Is_shidden(object) Bitfield_mask( 8,  1,object)
#define	Is_shiddenoverflow(object) Bitfield_mask( 7,  1,object)
#define	Is_slow(object) Bitfield_mask( 31,  1,object)
#define	Is_sbit24(object) Bitfield_mask( 24,  1,object)
#define	Is_sbit28(object) Bitfield_mask( 28,  1,object)
#define	Is_sbit29(object) Bitfield_mask( 29,  1,object)
#define	Is_sbit30(object) Bitfield_mask( 30,  1,object)
#define	Is_sbit31(object) Bitfield_mask( 31,  1,object)

/* 
 * Double number.
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |s|       exponent      |          mantissa part 1              |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 *
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |                    mantissa part 2                            |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 */
#define Dallp1(object) (object)
#define Dsign(object) Bitfield_extract( 0,  1,object)
#define Dsignedsign(object) Bitfield_signed_extract( 0,  1,object)
#define Dexponent(object) Bitfield_extract( 1,  11,object)
#define Dmantissap1(object) Bitfield_mask( 12, 20,object)
#define Dsignaling(object) Bitfield_extract( 12,  1,object)
#define Dsignalingnan(object) Bitfield_extract( 1,  12,object)
#define Dhigh2mantissa(object) Bitfield_extract( 12,  2,object)
#define Dexponentmantissap1(object) Bitfield_mask( 1, 31,object)
#define Dsignexponent(object) Bitfield_extract( 0, 12,object)
#define Dhidden(object) Bitfield_extract( 11,  1,object)
#define Dhiddenoverflow(object) Bitfield_extract( 10,  1,object)
#define Dhiddenhigh7mantissa(object) Bitfield_extract( 11,  8,object)
#define Dhiddenhigh3mantissa(object) Bitfield_extract( 11,  4,object)
#define Dlowp1(object) Bitfield_mask( 31,  1,object)
#define Dlow31p1(object) Bitfield_mask( 1, 31,object)
#define Dhighp1(object) Bitfield_extract( 0,  1,object)
#define Dhigh4p1(object) Bitfield_extract( 0,  4,object)
#define Dhigh31p1(object) Bitfield_extract( 0, 31,object)
#define Dsignedhigh31p1(object) Bitfield_signed_extract( 0, 31,object)
#define Dbit3p1(object) Bitfield_extract( 3,  1,object)

#define Deposit_dsign(object,value) Bitfield_deposit(value,0,1,object)
#define Deposit_dexponent(object,value) Bitfield_deposit(value,1,11,object)
#define Deposit_dmantissap1(object,value) Bitfield_deposit(value,12,20,object)
#define Deposit_dhigh2mantissa(object,value) Bitfield_deposit(value,12,2,object)
#define Deposit_dexponentmantissap1(object,value) \
    Bitfield_deposit(value,1,31,object)
#define Deposit_dsignexponent(object,value) Bitfield_deposit(value,0,12,object)
#define Deposit_dlowp1(object,value) Bitfield_deposit(value,31,1,object)
#define Deposit_dhigh4p1(object,value) Bitfield_deposit(value,0,4,object)

#define Is_dsign(object) Bitfield_mask( 0,  1,object)
#define Is_dsignaling(object) Bitfield_mask( 12,  1,object)
#define Is_dhidden(object) Bitfield_mask( 11,  1,object)
#define Is_dhiddenoverflow(object) Bitfield_mask( 10,  1,object)
#define Is_dlowp1(object) Bitfield_mask( 31,  1,object)
#define Is_dhighp1(object) Bitfield_mask( 0,  1,object)
#define Is_dbit3p1(object) Bitfield_mask( 3,  1,object)

#define Dallp2(object) (object)
#define Dmantissap2(object) (object)
#define Dlowp2(object) Bitfield_mask( 31,  1,object)
#define Dlow4p2(object) Bitfield_mask( 28,  4,object)
#define Dlow31p2(object) Bitfield_mask( 1, 31,object)
#define Dhighp2(object) Bitfield_extract( 0,  1,object)
#define Dhigh31p2(object) Bitfield_extract( 0, 31,object)
#define Dbit2p2(object) Bitfield_extract( 2,  1,object)
#define Dbit3p2(object) Bitfield_extract( 3,  1,object)
#define Dbit21p2(object) Bitfield_extract( 21,  1,object)
#define Dbit28p2(object) Bitfield_extract( 28,  1,object)
#define Dbit29p2(object) Bitfield_extract( 29,  1,object)
#define Dbit30p2(object) Bitfield_extract( 30,  1,object)
#define Dbit31p2(object) Bitfield_mask( 31,  1,object)

#define Deposit_dlowp2(object,value) Bitfield_deposit(value,31,1,object)

#define Is_dlowp2(object) Bitfield_mask( 31,  1,object)
#define Is_dhighp2(object) Bitfield_mask( 0,  1,object)
#define Is_dbit2p2(object) Bitfield_mask( 2,  1,object)
#define Is_dbit3p2(object) Bitfield_mask( 3,  1,object)
#define Is_dbit21p2(object) Bitfield_mask( 21,  1,object)
#define Is_dbit28p2(object) Bitfield_mask( 28,  1,object)
#define Is_dbit29p2(object) Bitfield_mask( 29,  1,object)
#define Is_dbit30p2(object) Bitfield_mask( 30,  1,object)
#define Is_dbit31p2(object) Bitfield_mask( 31,  1,object)

/* 
 * Quad number.
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |s|          exponent           |      mantissa part 1          |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 *
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |                    mantissa part 2                            |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 *
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |                    mantissa part 3                            |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 *
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |                    mantissa part 4                            |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 */
typedef struct
    {
    union
	{
	struct { unsigned qallp1; } u_qallp1;
/* Not needed for now...
	Bitfield_extract( 0,  1,u_qsign,qsign)
	Bitfield_signed_extract( 0,  1,u_qsignedsign,qsignedsign)
	Bitfield_extract( 1, 15,u_qexponent,qexponent)
	Bitfield_extract(16, 16,u_qmantissap1,qmantissap1)
	Bitfield_extract(16,  1,u_qsignaling,qsignaling)
	Bitfield_extract(1,  16,u_qsignalingnan,qsignalingnan)
	Bitfield_extract(16,  2,u_qhigh2mantissa,qhigh2mantissa)
	Bitfield_extract( 1, 31,u_qexponentmantissap1,qexponentmantissap1)
	Bitfield_extract( 0, 16,u_qsignexponent,qsignexponent)
	Bitfield_extract(15,  1,u_qhidden,qhidden)
	Bitfield_extract(14,  1,u_qhiddenoverflow,qhiddenoverflow)
	Bitfield_extract(15,  8,u_qhiddenhigh7mantissa,qhiddenhigh7mantissa)
	Bitfield_extract(15,  4,u_qhiddenhigh3mantissa,qhiddenhigh3mantissa)
	Bitfield_extract(31,  1,u_qlowp1,qlowp1)
	Bitfield_extract( 1, 31,u_qlow31p1,qlow31p1)
	Bitfield_extract( 0,  1,u_qhighp1,qhighp1)
	Bitfield_extract( 0,  4,u_qhigh4p1,qhigh4p1)
	Bitfield_extract( 0, 31,u_qhigh31p1,qhigh31p1)
  */
	} quad_u1;
    union
	{
	struct { unsigned qallp2; } u_qallp2;
  /* Not needed for now...
	Bitfield_extract(31,  1,u_qlowp2,qlowp2)
	Bitfield_extract( 1, 31,u_qlow31p2,qlow31p2)
	Bitfield_extract( 0,  1,u_qhighp2,qhighp2)
	Bitfield_extract( 0, 31,u_qhigh31p2,qhigh31p2)
   */
	} quad_u2;
    union
	{
	struct { unsigned qallp3; } u_qallp3;
  /* Not needed for now...
	Bitfield_extract(31,  1,u_qlowp3,qlowp3)
	Bitfield_extract( 1, 31,u_qlow31p3,qlow31p3)
	Bitfield_extract( 0,  1,u_qhighp3,qhighp3)
	Bitfield_extract( 0, 31,u_qhigh31p3,qhigh31p3)
   */ 
	} quad_u3;
    union
	{
	struct { unsigned qallp4; } u_qallp4;
    /* Not need for now...
	Bitfield_extract(31,  1,u_qlowp4,qlowp4)
	Bitfield_extract( 1, 31,u_qlow31p4,qlow31p4)
	Bitfield_extract( 0,  1,u_qhighp4,qhighp4)
	Bitfield_extract( 0, 31,u_qhigh31p4,qhigh31p4)
     */
	} quad_u4;
    } quad_floating_point;

/* Extension - An additional structure to hold the guard, round and
 *             sticky bits during computations.
 */
#define Extall(object) (object)
#define Extsign(object) Bitfield_extract( 0,  1,object)
#define Exthigh31(object) Bitfield_extract( 0, 31,object)
#define Extlow31(object) Bitfield_extract( 1, 31,object)
#define Extlow(object) Bitfield_extract( 31,  1,object)

/*
 * Single extended - The upper word is just like single precision,
 *                 but one additional word of mantissa is needed.
 */
#define Sextallp1(object) (object)
#define Sextallp2(object) (object)
#define Sextlowp1(object) Bitfield_extract( 31,  1,object)
#define Sexthighp2(object) Bitfield_extract( 0,  1,object)
#define Sextlow31p2(object) Bitfield_extract( 1, 31,object)
#define Sexthiddenoverflow(object) Bitfield_extract( 4,  1,object)
#define Is_sexthiddenoverflow(object) Bitfield_mask( 4,  1,object)

/*
 * Double extended - The upper two words are just like double precision,
 *		     but two additional words of mantissa are needed.
 */
#define Dextallp1(object) (object)
#define Dextallp2(object) (object)
#define Dextallp3(object) (object)
#define Dextallp4(object) (object)
#define Dextlowp2(object) Bitfield_extract( 31,  1,object)
#define Dexthighp3(object) Bitfield_extract( 0,  1,object)
#define Dextlow31p3(object) Bitfield_extract( 1, 31,object)