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/* flonum.h - Floating point package
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   Copyright (C) 1987-2015 Free Software Foundation, Inc.
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   This file is part of GAS, the GNU Assembler.
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   GAS is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; either version 3, or (at your option)
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   any later version.
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   GAS is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with GAS; see the file COPYING.  If not, write to the Free
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   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
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   02110-1301, USA.  */
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/***********************************************************************\
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 *									*
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 *	Arbitrary-precision floating point arithmetic.			*
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 *									*
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 *									*
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 *	Notation: a floating point number is expressed as		*
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 *	MANTISSA * (2 ** EXPONENT).					*
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 *									*
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 *	If this offends more traditional mathematicians, then		*
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 *	please tell me your nomenclature for flonums!			*
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 *									*
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 \***********************************************************************/
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#include "bignum.h"
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/***********************************************************************\
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 *									*
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 *	Variable precision floating point numbers.			*
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 *									*
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 *	Exponent is the place value of the low littlenum. E.g.:		*
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 *	If  0:  low points to the units             littlenum.		*
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 *	If  1:  low points to the LITTLENUM_RADIX   littlenum.		*
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 *	If -1:  low points to the 1/LITTLENUM_RADIX littlenum.		*
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 *									*
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 \***********************************************************************/
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/* JF:  A sign value of 0 means we have been asked to assemble NaN
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   A sign value of 'P' means we've been asked to assemble +Inf
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   A sign value of 'N' means we've been asked to assemble -Inf
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   */
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struct FLONUM_STRUCT {
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  LITTLENUM_TYPE *low;		/* low order littlenum of a bignum */
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  LITTLENUM_TYPE *high;		/* high order littlenum of a bignum */
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  LITTLENUM_TYPE *leader;	/* -> 1st non-zero littlenum */
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  /* If flonum is 0.0, leader==low-1 */
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  long exponent;		/* base LITTLENUM_RADIX */
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  char sign;			/* '+' or '-' */
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};
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typedef struct FLONUM_STRUCT FLONUM_TYPE;
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/***********************************************************************\
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 *									*
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 *	Since we can (& do) meet with exponents like 10^5000, it	*
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 *	is silly to make a table of ~ 10,000 entries, one for each	*
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 *	power of 10. We keep a table where item [n] is a struct		*
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 *	FLONUM_FLOATING_POINT representing 10^(2^n). We then		*
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 *	multiply appropriate entries from this table to get any		*
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 *	particular power of 10. For the example of 10^5000, a table	*
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 *	of just 25 entries suffices: 10^(2^-12)...10^(2^+12).		*
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 *									*
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 \***********************************************************************/
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extern const FLONUM_TYPE flonum_positive_powers_of_ten[];
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extern const FLONUM_TYPE flonum_negative_powers_of_ten[];
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extern const int table_size_of_flonum_powers_of_ten;
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/* Flonum_XXX_powers_of_ten[] table has legal indices from 0 to
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   + this number inclusive.  */
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/***********************************************************************\
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 *									*
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 *	Declare worker functions.					*
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 *									*
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 \***********************************************************************/
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int atof_generic (char **address_of_string_pointer,
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		  const char *string_of_decimal_marks,
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		  const char *string_of_decimal_exponent_marks,
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		  FLONUM_TYPE * address_of_generic_floating_point_number);
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void flonum_copy (FLONUM_TYPE * in, FLONUM_TYPE * out);
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void flonum_multip (const FLONUM_TYPE * a, const FLONUM_TYPE * b,
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		    FLONUM_TYPE * product);
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/***********************************************************************\
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 *									*
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 *	Declare error codes.						*
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 *									*
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 \***********************************************************************/
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#define ERROR_EXPONENT_OVERFLOW (2)