Subversion Repositories Kolibri OS

Rev

Rev 5222 | Only display areas with differences | Regard whitespace | Details | Blame | Last modification | View Log | RSS feed

Rev 5222 Rev 6324
1
/* flonum.h - Floating point package
1
/* flonum.h - Floating point package
2
   Copyright 1987, 1990, 1991, 1992, 1994, 1996, 2000, 2003, 2005, 2007
-
 
3
   Free Software Foundation, Inc.
2
   Copyright (C) 1987-2015 Free Software Foundation, Inc.
4
 
3
 
5
   This file is part of GAS, the GNU Assembler.
4
   This file is part of GAS, the GNU Assembler.
6
 
5
 
7
   GAS is free software; you can redistribute it and/or modify
6
   GAS is free software; you can redistribute it and/or modify
8
   it under the terms of the GNU General Public License as published by
7
   it under the terms of the GNU General Public License as published by
9
   the Free Software Foundation; either version 3, or (at your option)
8
   the Free Software Foundation; either version 3, or (at your option)
10
   any later version.
9
   any later version.
11
 
10
 
12
   GAS is distributed in the hope that it will be useful,
11
   GAS is distributed in the hope that it will be useful,
13
   but WITHOUT ANY WARRANTY; without even the implied warranty of
12
   but WITHOUT ANY WARRANTY; without even the implied warranty of
14
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15
   GNU General Public License for more details.
14
   GNU General Public License for more details.
16
 
15
 
17
   You should have received a copy of the GNU General Public License
16
   You should have received a copy of the GNU General Public License
18
   along with GAS; see the file COPYING.  If not, write to the Free
17
   along with GAS; see the file COPYING.  If not, write to the Free
19
   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
18
   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
20
   02110-1301, USA.  */
19
   02110-1301, USA.  */
21
 
20
 
22
/***********************************************************************\
21
/***********************************************************************\
23
 *									*
22
 *									*
24
 *	Arbitrary-precision floating point arithmetic.			*
23
 *	Arbitrary-precision floating point arithmetic.			*
25
 *									*
24
 *									*
26
 *									*
25
 *									*
27
 *	Notation: a floating point number is expressed as		*
26
 *	Notation: a floating point number is expressed as		*
28
 *	MANTISSA * (2 ** EXPONENT).					*
27
 *	MANTISSA * (2 ** EXPONENT).					*
29
 *									*
28
 *									*
30
 *	If this offends more traditional mathematicians, then		*
29
 *	If this offends more traditional mathematicians, then		*
31
 *	please tell me your nomenclature for flonums!			*
30
 *	please tell me your nomenclature for flonums!			*
32
 *									*
31
 *									*
33
 \***********************************************************************/
32
 \***********************************************************************/
34
 
33
 
35
#include "bignum.h"
34
#include "bignum.h"
36
 
35
 
37
/***********************************************************************\
36
/***********************************************************************\
38
 *									*
37
 *									*
39
 *	Variable precision floating point numbers.			*
38
 *	Variable precision floating point numbers.			*
40
 *									*
39
 *									*
41
 *	Exponent is the place value of the low littlenum. E.g.:		*
40
 *	Exponent is the place value of the low littlenum. E.g.:		*
42
 *	If  0:  low points to the units             littlenum.		*
41
 *	If  0:  low points to the units             littlenum.		*
43
 *	If  1:  low points to the LITTLENUM_RADIX   littlenum.		*
42
 *	If  1:  low points to the LITTLENUM_RADIX   littlenum.		*
44
 *	If -1:  low points to the 1/LITTLENUM_RADIX littlenum.		*
43
 *	If -1:  low points to the 1/LITTLENUM_RADIX littlenum.		*
45
 *									*
44
 *									*
46
 \***********************************************************************/
45
 \***********************************************************************/
47
 
46
 
48
/* JF:  A sign value of 0 means we have been asked to assemble NaN
47
/* JF:  A sign value of 0 means we have been asked to assemble NaN
49
   A sign value of 'P' means we've been asked to assemble +Inf
48
   A sign value of 'P' means we've been asked to assemble +Inf
50
   A sign value of 'N' means we've been asked to assemble -Inf
49
   A sign value of 'N' means we've been asked to assemble -Inf
51
   */
50
   */
52
struct FLONUM_STRUCT {
51
struct FLONUM_STRUCT {
53
  LITTLENUM_TYPE *low;		/* low order littlenum of a bignum */
52
  LITTLENUM_TYPE *low;		/* low order littlenum of a bignum */
54
  LITTLENUM_TYPE *high;		/* high order littlenum of a bignum */
53
  LITTLENUM_TYPE *high;		/* high order littlenum of a bignum */
55
  LITTLENUM_TYPE *leader;	/* -> 1st non-zero littlenum */
54
  LITTLENUM_TYPE *leader;	/* -> 1st non-zero littlenum */
56
  /* If flonum is 0.0, leader==low-1 */
55
  /* If flonum is 0.0, leader==low-1 */
57
  long exponent;		/* base LITTLENUM_RADIX */
56
  long exponent;		/* base LITTLENUM_RADIX */
58
  char sign;			/* '+' or '-' */
57
  char sign;			/* '+' or '-' */
59
};
58
};
60
 
59
 
61
typedef struct FLONUM_STRUCT FLONUM_TYPE;
60
typedef struct FLONUM_STRUCT FLONUM_TYPE;
62
 
61
 
63
/***********************************************************************\
62
/***********************************************************************\
64
 *									*
63
 *									*
65
 *	Since we can (& do) meet with exponents like 10^5000, it	*
64
 *	Since we can (& do) meet with exponents like 10^5000, it	*
66
 *	is silly to make a table of ~ 10,000 entries, one for each	*
65
 *	is silly to make a table of ~ 10,000 entries, one for each	*
67
 *	power of 10. We keep a table where item [n] is a struct		*
66
 *	power of 10. We keep a table where item [n] is a struct		*
68
 *	FLONUM_FLOATING_POINT representing 10^(2^n). We then		*
67
 *	FLONUM_FLOATING_POINT representing 10^(2^n). We then		*
69
 *	multiply appropriate entries from this table to get any		*
68
 *	multiply appropriate entries from this table to get any		*
70
 *	particular power of 10. For the example of 10^5000, a table	*
69
 *	particular power of 10. For the example of 10^5000, a table	*
71
 *	of just 25 entries suffices: 10^(2^-12)...10^(2^+12).		*
70
 *	of just 25 entries suffices: 10^(2^-12)...10^(2^+12).		*
72
 *									*
71
 *									*
73
 \***********************************************************************/
72
 \***********************************************************************/
74
 
73
 
75
extern const FLONUM_TYPE flonum_positive_powers_of_ten[];
74
extern const FLONUM_TYPE flonum_positive_powers_of_ten[];
76
extern const FLONUM_TYPE flonum_negative_powers_of_ten[];
75
extern const FLONUM_TYPE flonum_negative_powers_of_ten[];
77
extern const int table_size_of_flonum_powers_of_ten;
76
extern const int table_size_of_flonum_powers_of_ten;
78
/* Flonum_XXX_powers_of_ten[] table has legal indices from 0 to
77
/* Flonum_XXX_powers_of_ten[] table has legal indices from 0 to
79
   + this number inclusive.  */
78
   + this number inclusive.  */
80
 
79
 
81
/***********************************************************************\
80
/***********************************************************************\
82
 *									*
81
 *									*
83
 *	Declare worker functions.					*
82
 *	Declare worker functions.					*
84
 *									*
83
 *									*
85
 \***********************************************************************/
84
 \***********************************************************************/
86
 
85
 
87
int atof_generic (char **address_of_string_pointer,
86
int atof_generic (char **address_of_string_pointer,
88
		  const char *string_of_decimal_marks,
87
		  const char *string_of_decimal_marks,
89
		  const char *string_of_decimal_exponent_marks,
88
		  const char *string_of_decimal_exponent_marks,
90
		  FLONUM_TYPE * address_of_generic_floating_point_number);
89
		  FLONUM_TYPE * address_of_generic_floating_point_number);
91
 
90
 
92
void flonum_copy (FLONUM_TYPE * in, FLONUM_TYPE * out);
91
void flonum_copy (FLONUM_TYPE * in, FLONUM_TYPE * out);
93
void flonum_multip (const FLONUM_TYPE * a, const FLONUM_TYPE * b,
92
void flonum_multip (const FLONUM_TYPE * a, const FLONUM_TYPE * b,
94
		    FLONUM_TYPE * product);
93
		    FLONUM_TYPE * product);
95
 
94
 
96
/***********************************************************************\
95
/***********************************************************************\
97
 *									*
96
 *									*
98
 *	Declare error codes.						*
97
 *	Declare error codes.						*
99
 *									*
98
 *									*
100
 \***********************************************************************/
99
 \***********************************************************************/
101
 
100
 
102
#define ERROR_EXPONENT_OVERFLOW (2)
101
#define ERROR_EXPONENT_OVERFLOW (2)