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gcc_float.h
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1/* Copyright (C) 2002 Free Software Foundation, Inc.
2
3This file is part of GCC.
4
5GCC is free software; you can redistribute it and/or modify
6it under the terms of the GNU General Public License as published by
7the Free Software Foundation; either version 2, or (at your option)
8any later version.
9
10GCC is distributed in the hope that it will be useful,
11but WITHOUT ANY WARRANTY; without even the implied warranty of
12MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13GNU General Public License for more details.
14
15You should have received a copy of the GNU General Public License
16along with GCC; see the file COPYING. If not, write to
17the Free Software Foundation, 51 Franklin Street, Fifth Floor,
18Boston, MA 02110-1301, USA. */
19
20/* As a special exception, if you include this header file into source
21 files compiled by GCC, this header file does not by itself cause
22 the resulting executable to be covered by the GNU General Public
23 License. This exception does not however invalidate any other
24 reasons why the executable file might be covered by the GNU General
25 Public License. */
26
27/*
28 * ISO C Standard: 5.2.4.2.2 Characteristics of floating types <float.h>
29 */
30
31#ifndef _FLOAT_H___
32#define _FLOAT_H___
33
34/* Radix of exponent representation, b. */
35#undef FLT_RADIX
36#define FLT_RADIX __FLT_RADIX__
37
38/* Number of base-FLT_RADIX digits in the significand, p. */
39#undef FLT_MANT_DIG
40#undef DBL_MANT_DIG
41#undef LDBL_MANT_DIG
42#define FLT_MANT_DIG __FLT_MANT_DIG__
43#define DBL_MANT_DIG __DBL_MANT_DIG__
44#define LDBL_MANT_DIG __LDBL_MANT_DIG__
45
46/* Number of decimal digits, q, such that any floating-point number with q
47 decimal digits can be rounded into a floating-point number with p radix b
48 digits and back again without change to the q decimal digits,
49
50 p * log10(b) if b is a power of 10
51 floor((p - 1) * log10(b)) otherwise
52*/
53#undef FLT_DIG
54#undef DBL_DIG
55#undef LDBL_DIG
56#define FLT_DIG __FLT_DIG__
57#define DBL_DIG __DBL_DIG__
58#define LDBL_DIG __LDBL_DIG__
59
60/* Minimum int x such that FLT_RADIX**(x-1) is a normalized float, emin */
61#undef FLT_MIN_EXP
62#undef DBL_MIN_EXP
63#undef LDBL_MIN_EXP
64#define FLT_MIN_EXP __FLT_MIN_EXP__
65#define DBL_MIN_EXP __DBL_MIN_EXP__
66#define LDBL_MIN_EXP __LDBL_MIN_EXP__
67
68/* Minimum negative integer such that 10 raised to that power is in the
69 range of normalized floating-point numbers,
70
71 ceil(log10(b) * (emin - 1))
72*/
73#undef FLT_MIN_10_EXP
74#undef DBL_MIN_10_EXP
75#undef LDBL_MIN_10_EXP
76#define FLT_MIN_10_EXP __FLT_MIN_10_EXP__
77#define DBL_MIN_10_EXP __DBL_MIN_10_EXP__
78#define LDBL_MIN_10_EXP __LDBL_MIN_10_EXP__
79
80/* Maximum int x such that FLT_RADIX**(x-1) is a representable float, emax. */
81#undef FLT_MAX_EXP
82#undef DBL_MAX_EXP
83#undef LDBL_MAX_EXP
84#define FLT_MAX_EXP __FLT_MAX_EXP__
85#define DBL_MAX_EXP __DBL_MAX_EXP__
86#define LDBL_MAX_EXP __LDBL_MAX_EXP__
87
88/* Maximum integer such that 10 raised to that power is in the range of
89 representable finite floating-point numbers,
90
91 floor(log10((1 - b**-p) * b**emax))
92*/
93#undef FLT_MAX_10_EXP
94#undef DBL_MAX_10_EXP
95#undef LDBL_MAX_10_EXP
96#define FLT_MAX_10_EXP __FLT_MAX_10_EXP__
97#define DBL_MAX_10_EXP __DBL_MAX_10_EXP__
98#define LDBL_MAX_10_EXP __LDBL_MAX_10_EXP__
99
100/* Maximum representable finite floating-point number,
101
102 (1 - b**-p) * b**emax
103*/
104#undef FLT_MAX
105#undef DBL_MAX
106#undef LDBL_MAX
107#define FLT_MAX __FLT_MAX__
108#define DBL_MAX __DBL_MAX__
109#define LDBL_MAX __LDBL_MAX__
110
111/* The difference between 1 and the least value greater than 1 that is
112 representable in the given floating point type, b**1-p. */
113#undef FLT_EPSILON
114#undef DBL_EPSILON
115#undef LDBL_EPSILON
116#define FLT_EPSILON __FLT_EPSILON__
117#define DBL_EPSILON __DBL_EPSILON__
118#define LDBL_EPSILON __LDBL_EPSILON__
119
120/* Minimum normalized positive floating-point number, b**(emin - 1). */
121#undef FLT_MIN
122#undef DBL_MIN
123#undef LDBL_MIN
124#define FLT_MIN __FLT_MIN__
125#define DBL_MIN __DBL_MIN__
126#define LDBL_MIN __LDBL_MIN__
127
128/* Addition rounds to 0: zero, 1: nearest, 2: +inf, 3: -inf, -1: unknown. */
129/* ??? This is supposed to change with calls to fesetround in <fenv.h>. */
130#undef FLT_ROUNDS
131#define FLT_ROUNDS 1
132
133#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
134/* The floating-point expression evaluation method.
135 -1 indeterminate
136 0 evaluate all operations and constants just to the range and
137 precision of the type
138 1 evaluate operations and constants of type float and double
139 to the range and precision of the double type, evaluate
140 long double operations and constants to the range and
141 precision of the long double type
142 2 evaluate all operations and constants to the range and
143 precision of the long double type
144
145 ??? This ought to change with the setting of the fp control word;
146 the value provided by the compiler assumes the widest setting. */
147#undef FLT_EVAL_METHOD
148#define FLT_EVAL_METHOD __FLT_EVAL_METHOD__
149
150/* Number of decimal digits, n, such that any floating-point number in the
151 widest supported floating type with pmax radix b digits can be rounded
152 to a floating-point number with n decimal digits and back again without
153 change to the value,
154
155 pmax * log10(b) if b is a power of 10
156 ceil(1 + pmax * log10(b)) otherwise
157*/
158#undef DECIMAL_DIG
159#define DECIMAL_DIG __DECIMAL_DIG__
160
161#endif /* C99 */
162#endif /* _FLOAT_H___ */