[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 2, 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.  */

/***********************************************************************\
 *									*
 *	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 of flonum.h */
Commit	Line	Data
fecd2382 RP	1	/* flonum.h - Floating point package
fecd2382 RP	2	Copyright (C) 1987, 1990, 1991 Free Software Foundation, Inc.
a39116f1 RP	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 2, 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. */
fecd2382	19
fecd2382	20	/***********************************************************************\
a39116f1 RP	21	* *
	22	* Arbitrary-precision floating point arithmetic. *
	23	* *
	24	* *
	25	* Notation: a floating point number is expressed as *
	26	* MANTISSA * (2 ** EXPONENT). *
	27	* *
	28	* If this offends more traditional mathematicians, then *
	29	* please tell me your nomenclature for flonums! *
	30	* *
	31	\***********************************************************************/
fecd2382 RP	32	#if !defined(__STDC__) && !defined(const)
	33	#define const /* empty */
	34	#endif
	35
	36	#include "bignum.h"
	37
	38	/***********************************************************************\
a39116f1 RP	39	* *
	40	* Variable precision floating point numbers. *
	41	* *
	42	* Exponent is the place value of the low littlenum. E.g.: *
	43	* If 0: low points to the units littlenum. *
	44	* If 1: low points to the LITTLENUM_RADIX littlenum. *
	45	* If -1: low points to the 1/LITTLENUM_RADIX littlenum. *
	46	* *
	47	\***********************************************************************/
fecd2382 RP	48
	49	/* JF: A sign value of 0 means we have been asked to assemble NaN
	50	A sign value of 'P' means we've been asked to assemble +Inf
	51	A sign value of 'N' means we've been asked to assemble -Inf
a39116f1	52	*/
fecd2382 RP	53	struct FLONUM_STRUCT
fecd2382 RP	54	{
a39116f1 RP	55	LITTLENUM_TYPE * low; /* low order littlenum of a bignum */
	56	LITTLENUM_TYPE * high; /* high order littlenum of a bignum */
	57	LITTLENUM_TYPE * leader; /* -> 1st non-zero littlenum */
	58	/* If flonum is 0.0, leader==low-1 */
	59	long exponent; /* base LITTLENUM_RADIX */
	60	char sign; /* '+' or '-' */
fecd2382 RP	61	};
	62
	63	typedef struct FLONUM_STRUCT FLONUM_TYPE;
	64
	65
	66	/***********************************************************************\
a39116f1 RP	67	* *
	68	* Since we can (& do) meet with exponents like 10^5000, it *
	69	* is silly to make a table of ~ 10,000 entries, one for each *
	70	* power of 10. We keep a table where item [n] is a struct *
	71	* FLONUM_FLOATING_POINT representing 10^(2^n). We then *
	72	* multiply appropriate entries from this table to get any *
	73	* particular power of 10. For the example of 10^5000, a table *
	74	* of just 25 entries suffices: 10^(2^-12)...10^(2^+12). *
	75	* *
	76	\***********************************************************************/
fecd2382 RP	77
	78
	79	extern const FLONUM_TYPE flonum_positive_powers_of_ten[];
	80	extern const FLONUM_TYPE flonum_negative_powers_of_ten[];
	81	extern const int table_size_of_flonum_powers_of_ten;
a39116f1 RP	82	/* Flonum_XXX_powers_of_ten[] table has */
	83	/* legal indices from 0 to */
	84	/* + this number inclusive. */
fecd2382 RP	85
	86
	87
	88	/***********************************************************************\
a39116f1 RP	89	* *
	90	* Declare worker functions. *
	91	* *
	92	\***********************************************************************/
fecd2382 RP	93
	94	#ifdef __STDC__
	95
	96	int atof_generic(char **address_of_string_pointer,
	97	const char *string_of_decimal_marks,
	98	const char *string_of_decimal_exponent_marks,
	99	FLONUM_TYPE *address_of_generic_floating_point_number);
	100
	101	void flonum_copy(FLONUM_TYPE in, FLONUM_TYPE out);
	102	void flonum_multip(const FLONUM_TYPE a, const FLONUM_TYPE b, FLONUM_TYPE *product);
	103
	104	#else /* __STDC__ */
	105
	106	int atof_generic();
	107	void flonum_copy();
	108	void flonum_multip();
	109
	110	#endif /* __STDC__ */
	111
	112	/***********************************************************************\
a39116f1 RP	113	* *
	114	* Declare error codes. *
	115	* *
	116	\***********************************************************************/
fecd2382 RP	117
	118	#define ERROR_EXPONENT_OVERFLOW (2)
	119
8b228fe9	120	/* end of flonum.h */