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Diffstat (limited to 'gnu/usr.bin/as/flonum.h')
| -rw-r--r-- | gnu/usr.bin/as/flonum.h | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/gnu/usr.bin/as/flonum.h b/gnu/usr.bin/as/flonum.h new file mode 100644 index 000000000000..6135c449d652 --- /dev/null +++ b/gnu/usr.bin/as/flonum.h @@ -0,0 +1,125 @@ +/* flonum.h - Floating point package + + Copyright (C) 1987, 1990, 1991, 1992 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. */ +/* + * $Id: flonum.h,v 1.2 1993/11/03 00:51:37 paul Exp $ + */ + + +/***********************************************************************\ + * * + * 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 (__STDC__ != 1) && !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. * + * * + \***********************************************************************/ + +#if __STDC__ == 1 + +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 /* not __STDC__ */ + +int atof_generic(); +void flonum_copy(); +void flonum_multip(); + +#endif /* not __STDC__ */ + +/***********************************************************************\ + * * + * Declare error codes. * + * * + \***********************************************************************/ + +#define ERROR_EXPONENT_OVERFLOW (2) + +/* end of flonum.h */ |