[binutils.git] / gas / flonum.h

/* flonum.h - Floating point package
   Copyright (C) 1987, 1990, 1991 Free Software Foundation, Inc.

This file is part of GAS, the GNU Assembler.

GAS 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 1, or (at your option)
any later version.

GAS 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 GAS; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* $Id$ */

/***********************************************************************\
*									*
*	Arbitrary-precision floating point arithmetic.			*
*									*
*									*
*	Notation: a floating point number is expressed as		*
*	MANTISSA * (2 ** EXPONENT).					*
*									*
*	If this offends more traditional mathematicians, then		*
*	please tell me your nomenclature for flonums!			*
*									*
\***********************************************************************/
#if !defined(__STDC__) && !defined(const)
#define const /* empty */
#endif

#include "bignum.h"

/***********************************************************************\
*									*
*	Variable precision floating point numbers.			*
*									*
*	Exponent is the place value of the low littlenum. E.g.:		*
*	If  0:  low points to the units             littlenum.		*
*	If  1:  low points to the LITTLENUM_RADIX   littlenum.		*
*	If -1:  low points to the 1/LITTLENUM_RADIX littlenum.		*
*									*
\***********************************************************************/

/* JF:  A sign value of 0 means we have been asked to assemble NaN
   A sign value of 'P' means we've been asked to assemble +Inf
   A sign value of 'N' means we've been asked to assemble -Inf
 */
struct FLONUM_STRUCT
{
  LITTLENUM_TYPE *	low;	/* low order littlenum of a bignum */
  LITTLENUM_TYPE *	high;	/* high order littlenum of a bignum */
  LITTLENUM_TYPE *	leader;	/* -> 1st non-zero littlenum */
				/* If flonum is 0.0, leader==low-1 */
  long		exponent; /* base LITTLENUM_RADIX */
  char			sign;	/* '+' or '-' */
};

typedef struct FLONUM_STRUCT FLONUM_TYPE;


/***********************************************************************\
*									*
*	Since we can (& do) meet with exponents like 10^5000, it	*
*	is silly to make a table of ~ 10,000 entries, one for each	*
*	power of 10. We keep a table where item [n] is a struct		*
*	FLONUM_FLOATING_POINT representing 10^(2^n). We then		*
*	multiply appropriate entries from this table to get any		*
*	particular power of 10. For the example of 10^5000, a table	*
*	of just 25 entries suffices: 10^(2^-12)...10^(2^+12).		*
*									*
\***********************************************************************/


extern const FLONUM_TYPE flonum_positive_powers_of_ten[];
extern const FLONUM_TYPE flonum_negative_powers_of_ten[];
extern const int table_size_of_flonum_powers_of_ten;
				/* Flonum_XXX_powers_of_ten[] table has */
				/* legal indices from 0 to */
				/* + this number inclusive. */


/***********************************************************************\
*									*
*	Declare worker functions.					*
*									*
\***********************************************************************/

#ifdef __STDC__

int atof_generic(char **address_of_string_pointer,
		 const char *string_of_decimal_marks,
		 const char *string_of_decimal_exponent_marks,
		 FLONUM_TYPE *address_of_generic_floating_point_number);

void flonum_copy(FLONUM_TYPE *in, FLONUM_TYPE *out);
void flonum_multip(const FLONUM_TYPE *a, const FLONUM_TYPE *b, FLONUM_TYPE *product);

#else /* __STDC__ */

int atof_generic();
void flonum_copy();
void flonum_multip();

#endif /* __STDC__ */

/***********************************************************************\
*									*
*	Declare error codes.						*
*									*
\***********************************************************************/

#define ERROR_EXPONENT_OVERFLOW (2)

/* end: flonum.h */
Commit	Line	Data
fecd2382 RP	1	/* flonum.h - Floating point package
	2	Copyright (C) 1987, 1990, 1991 Free Software Foundation, Inc.
	3
	4	This file is part of GAS, the GNU Assembler.
	5
	6	GAS is free software; you can redistribute it and/or modify
	7	it under the terms of the GNU General Public License as published by
	8	the Free Software Foundation; either version 1, or (at your option)
	9	any later version.
	10
	11	GAS is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with GAS; see the file COPYING. If not, write to
	18	the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
	19
	20	/* $Id$ */
	21
	22	/***********************************************************************\
	23	* *
	24	* Arbitrary-precision floating point arithmetic. *
	25	* *
	26	* *
	27	* Notation: a floating point number is expressed as *
	28	* MANTISSA * (2 ** EXPONENT). *
	29	* *
	30	* If this offends more traditional mathematicians, then *
	31	* please tell me your nomenclature for flonums! *
	32	* *
	33	\***********************************************************************/
	34	#if !defined(__STDC__) && !defined(const)
	35	#define const /* empty */
	36	#endif
	37
	38	#include "bignum.h"
	39
	40	/***********************************************************************\
	41	* *
	42	* Variable precision floating point numbers. *
	43	* *
	44	* Exponent is the place value of the low littlenum. E.g.: *
	45	* If 0: low points to the units littlenum. *
	46	* If 1: low points to the LITTLENUM_RADIX littlenum. *
	47	* If -1: low points to the 1/LITTLENUM_RADIX littlenum. *
	48	* *
	49	\***********************************************************************/
	50
	51	/* JF: A sign value of 0 means we have been asked to assemble NaN
	52	A sign value of 'P' means we've been asked to assemble +Inf
	53	A sign value of 'N' means we've been asked to assemble -Inf
	54	*/
	55	struct FLONUM_STRUCT
	56	{
	57	LITTLENUM_TYPE * low; /* low order littlenum of a bignum */
	58	LITTLENUM_TYPE * high; /* high order littlenum of a bignum */
	59	LITTLENUM_TYPE * leader; /* -> 1st non-zero littlenum */
	60	/* If flonum is 0.0, leader==low-1 */
	61	long exponent; /* base LITTLENUM_RADIX */
	62	char sign; /* '+' or '-' */
	63	};
	64
65	typedef struct FLONUM_STRUCT FLONUM_TYPE;
66
67
68	/***********************************************************************\
69	* *
70	* Since we can (& do) meet with exponents like 10^5000, it *
71	* is silly to make a table of ~ 10,000 entries, one for each *
72	* power of 10. We keep a table where item [n] is a struct *
73	* FLONUM_FLOATING_POINT representing 10^(2^n). We then *
74	* multiply appropriate entries from this table to get any *
75	* particular power of 10. For the example of 10^5000, a table *
76	* of just 25 entries suffices: 10^(2^-12)...10^(2^+12). *
77	* *
78	\***********************************************************************/
79
80
81	extern const FLONUM_TYPE flonum_positive_powers_of_ten[];
82	extern const FLONUM_TYPE flonum_negative_powers_of_ten[];
83	extern const int table_size_of_flonum_powers_of_ten;
84	/* Flonum_XXX_powers_of_ten[] table has */
85	/* legal indices from 0 to */
86	/* + this number inclusive. */
87
88
89
90	/***********************************************************************\
91	* *
92	* Declare worker functions. *
93	* *
94	\***********************************************************************/
95
96	#ifdef __STDC__
97
98	int atof_generic(char **address_of_string_pointer,
99	const char *string_of_decimal_marks,
100	const char *string_of_decimal_exponent_marks,
101	FLONUM_TYPE *address_of_generic_floating_point_number);
102
103	void flonum_copy(FLONUM_TYPE in, FLONUM_TYPE out);
104	void flonum_multip(const FLONUM_TYPE a, const FLONUM_TYPE b, FLONUM_TYPE *product);
105
106	#else /* __STDC__ */
107
108	int atof_generic();
109	void flonum_copy();
110	void flonum_multip();
111
112	#endif /* __STDC__ */
113
114	/***********************************************************************\
115	* *
116	* Declare error codes. *
117	* *
118	\***********************************************************************/
119
120	#define ERROR_EXPONENT_OVERFLOW (2)
121
122	/* end: flonum.h */