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      1 /* Copyright (C) 2002, 2007, 2008, 2009 Free Software Foundation, Inc.
      2 
      3 This file is part of GCC.
      4 
      5 GCC is free software; you can redistribute it and/or modify
      6 it under the terms of the GNU General Public License as published by
      7 the Free Software Foundation; either version 3, or (at your option)
      8 any later version.
      9 
     10 GCC is distributed in the hope that it will be useful,
     11 but WITHOUT ANY WARRANTY; without even the implied warranty of
     12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     13 GNU General Public License for more details.
     14 
     15 Under Section 7 of GPL version 3, you are granted additional
     16 permissions described in the GCC Runtime Library Exception, version
     17 3.1, as published by the Free Software Foundation.
     18 
     19 You should have received a copy of the GNU General Public License and
     20 a copy of the GCC Runtime Library Exception along with this program;
     21 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
     22 <http://www.gnu.org/licenses/>.  */
     23 
     24 /*
     25  * ISO C Standard:  5.2.4.2.2  Characteristics of floating types <float.h>
     26  */
     27 
     28 #ifndef _FLOAT_H___
     29 #define _FLOAT_H___
     30 
     31 /* Radix of exponent representation, b. */
     32 #undef FLT_RADIX
     33 #define FLT_RADIX	__FLT_RADIX__
     34 
     35 /* Number of base-FLT_RADIX digits in the significand, p.  */
     36 #undef FLT_MANT_DIG
     37 #undef DBL_MANT_DIG
     38 #undef LDBL_MANT_DIG
     39 #define FLT_MANT_DIG	__FLT_MANT_DIG__
     40 #define DBL_MANT_DIG	__DBL_MANT_DIG__
     41 #define LDBL_MANT_DIG	__LDBL_MANT_DIG__
     42 
     43 /* Number of decimal digits, q, such that any floating-point number with q
     44    decimal digits can be rounded into a floating-point number with p radix b
     45    digits and back again without change to the q decimal digits,
     46 
     47 	p * log10(b)			if b is a power of 10
     48 	floor((p - 1) * log10(b))	otherwise
     49 */
     50 #undef FLT_DIG
     51 #undef DBL_DIG
     52 #undef LDBL_DIG
     53 #define FLT_DIG		__FLT_DIG__
     54 #define DBL_DIG		__DBL_DIG__
     55 #define LDBL_DIG	__LDBL_DIG__
     56 
     57 /* Minimum int x such that FLT_RADIX**(x-1) is a normalized float, emin */
     58 #undef FLT_MIN_EXP
     59 #undef DBL_MIN_EXP
     60 #undef LDBL_MIN_EXP
     61 #define FLT_MIN_EXP	__FLT_MIN_EXP__
     62 #define DBL_MIN_EXP	__DBL_MIN_EXP__
     63 #define LDBL_MIN_EXP	__LDBL_MIN_EXP__
     64 
     65 /* Minimum negative integer such that 10 raised to that power is in the
     66    range of normalized floating-point numbers,
     67 
     68 	ceil(log10(b) * (emin - 1))
     69 */
     70 #undef FLT_MIN_10_EXP
     71 #undef DBL_MIN_10_EXP
     72 #undef LDBL_MIN_10_EXP
     73 #define FLT_MIN_10_EXP	__FLT_MIN_10_EXP__
     74 #define DBL_MIN_10_EXP	__DBL_MIN_10_EXP__
     75 #define LDBL_MIN_10_EXP	__LDBL_MIN_10_EXP__
     76 
     77 /* Maximum int x such that FLT_RADIX**(x-1) is a representable float, emax.  */
     78 #undef FLT_MAX_EXP
     79 #undef DBL_MAX_EXP
     80 #undef LDBL_MAX_EXP
     81 #define FLT_MAX_EXP	__FLT_MAX_EXP__
     82 #define DBL_MAX_EXP	__DBL_MAX_EXP__
     83 #define LDBL_MAX_EXP	__LDBL_MAX_EXP__
     84 
     85 /* Maximum integer such that 10 raised to that power is in the range of
     86    representable finite floating-point numbers,
     87 
     88 	floor(log10((1 - b**-p) * b**emax))
     89 */
     90 #undef FLT_MAX_10_EXP
     91 #undef DBL_MAX_10_EXP
     92 #undef LDBL_MAX_10_EXP
     93 #define FLT_MAX_10_EXP	__FLT_MAX_10_EXP__
     94 #define DBL_MAX_10_EXP	__DBL_MAX_10_EXP__
     95 #define LDBL_MAX_10_EXP	__LDBL_MAX_10_EXP__
     96 
     97 /* Maximum representable finite floating-point number,
     98 
     99 	(1 - b**-p) * b**emax
    100 */
    101 #undef FLT_MAX
    102 #undef DBL_MAX
    103 #undef LDBL_MAX
    104 #define FLT_MAX		__FLT_MAX__
    105 #define DBL_MAX		__DBL_MAX__
    106 #define LDBL_MAX	__LDBL_MAX__
    107 
    108 /* The difference between 1 and the least value greater than 1 that is
    109    representable in the given floating point type, b**1-p.  */
    110 #undef FLT_EPSILON
    111 #undef DBL_EPSILON
    112 #undef LDBL_EPSILON
    113 #define FLT_EPSILON	__FLT_EPSILON__
    114 #define DBL_EPSILON	__DBL_EPSILON__
    115 #define LDBL_EPSILON	__LDBL_EPSILON__
    116 
    117 /* Minimum normalized positive floating-point number, b**(emin - 1).  */
    118 #undef FLT_MIN
    119 #undef DBL_MIN
    120 #undef LDBL_MIN
    121 #define FLT_MIN		__FLT_MIN__
    122 #define DBL_MIN		__DBL_MIN__
    123 #define LDBL_MIN	__LDBL_MIN__
    124 
    125 /* Addition rounds to 0: zero, 1: nearest, 2: +inf, 3: -inf, -1: unknown.  */
    126 /* ??? This is supposed to change with calls to fesetround in <fenv.h>.  */
    127 #undef FLT_ROUNDS
    128 #define FLT_ROUNDS 1
    129 
    130 #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
    131 /* The floating-point expression evaluation method.
    132         -1  indeterminate
    133          0  evaluate all operations and constants just to the range and
    134             precision of the type
    135          1  evaluate operations and constants of type float and double
    136             to the range and precision of the double type, evaluate
    137             long double operations and constants to the range and
    138             precision of the long double type
    139          2  evaluate all operations and constants to the range and
    140             precision of the long double type
    141 
    142    ??? This ought to change with the setting of the fp control word;
    143    the value provided by the compiler assumes the widest setting.  */
    144 #undef FLT_EVAL_METHOD
    145 #define FLT_EVAL_METHOD	__FLT_EVAL_METHOD__
    146 
    147 /* Number of decimal digits, n, such that any floating-point number in the
    148    widest supported floating type with pmax radix b digits can be rounded
    149    to a floating-point number with n decimal digits and back again without
    150    change to the value,
    151 
    152 	pmax * log10(b)			if b is a power of 10
    153 	ceil(1 + pmax * log10(b))	otherwise
    154 */
    155 #undef DECIMAL_DIG
    156 #define DECIMAL_DIG	__DECIMAL_DIG__
    157 
    158 #endif /* C99 */
    159 
    160 #ifdef __STDC_WANT_DEC_FP__
    161 /* Draft Technical Report 24732, extension for decimal floating-point
    162    arithmetic: Characteristic of decimal floating types <float.h>.  */
    163 
    164 /* Number of base-FLT_RADIX digits in the significand, p.  */
    165 #undef DEC32_MANT_DIG
    166 #undef DEC64_MANT_DIG
    167 #undef DEC128_MANT_DIG
    168 #define DEC32_MANT_DIG	__DEC32_MANT_DIG__
    169 #define DEC64_MANT_DIG	__DEC64_MANT_DIG__
    170 #define DEC128_MANT_DIG	__DEC128_MANT_DIG__
    171 
    172 /* Minimum exponent. */
    173 #undef DEC32_MIN_EXP
    174 #undef DEC64_MIN_EXP
    175 #undef DEC128_MIN_EXP
    176 #define DEC32_MIN_EXP	__DEC32_MIN_EXP__
    177 #define DEC64_MIN_EXP	__DEC64_MIN_EXP__
    178 #define DEC128_MIN_EXP	__DEC128_MIN_EXP__
    179 
    180 /* Maximum exponent. */
    181 #undef DEC32_MAX_EXP
    182 #undef DEC64_MAX_EXP
    183 #undef DEC128_MAX_EXP
    184 #define DEC32_MAX_EXP	__DEC32_MAX_EXP__
    185 #define DEC64_MAX_EXP	__DEC64_MAX_EXP__
    186 #define DEC128_MAX_EXP	__DEC128_MAX_EXP__
    187 
    188 /* Maximum representable finite decimal floating-point number
    189    (there are 6, 15, and 33 9s after the decimal points respectively). */
    190 #undef DEC32_MAX
    191 #undef DEC64_MAX
    192 #undef DEC128_MAX
    193 #define DEC32_MAX   __DEC32_MAX__
    194 #define DEC64_MAX   __DEC64_MAX__
    195 #define DEC128_MAX  __DEC128_MAX__
    196 
    197 /* The difference between 1 and the least value greater than 1 that is
    198    representable in the given floating point type. */
    199 #undef DEC32_EPSILON
    200 #undef DEC64_EPSILON
    201 #undef DEC128_EPSILON
    202 #define DEC32_EPSILON	__DEC32_EPSILON__
    203 #define DEC64_EPSILON	__DEC64_EPSILON__
    204 #define DEC128_EPSILON	__DEC128_EPSILON__
    205 
    206 /* Minimum normalized positive floating-point number. */
    207 #undef DEC32_MIN
    208 #undef DEC64_MIN
    209 #undef DEC128_MIN
    210 #define DEC32_MIN	__DEC32_MIN__
    211 #define DEC64_MIN	__DEC64_MIN__
    212 #define DEC128_MIN	__DEC128_MIN__
    213 
    214 /* Minimum subnormal positive floating-point number. */
    215 #undef DEC32_SUBNORMAL_MIN
    216 #undef DEC64_SUBNORMAL_MIN
    217 #undef DEC128_SUBNORMAL_MIN
    218 #define DEC32_SUBNORMAL_MIN       __DEC32_SUBNORMAL_MIN__
    219 #define DEC64_SUBNORMAL_MIN       __DEC64_SUBNORMAL_MIN__
    220 #define DEC128_SUBNORMAL_MIN      __DEC128_SUBNORMAL_MIN__
    221 
    222 /* The floating-point expression evaluation method.
    223          -1  indeterminate
    224          0  evaluate all operations and constants just to the range and
    225             precision of the type
    226          1  evaluate operations and constants of type _Decimal32
    227 	    and _Decimal64 to the range and precision of the _Decimal64
    228             type, evaluate _Decimal128 operations and constants to the
    229 	    range and precision of the _Decimal128 type;
    230 	 2  evaluate all operations and constants to the range and
    231 	    precision of the _Decimal128 type.  */
    232 
    233 #undef DEC_EVAL_METHOD
    234 #define DEC_EVAL_METHOD	__DEC_EVAL_METHOD__
    235 
    236 #endif /* __STDC_WANT_DEC_FP__ */
    237 
    238 #endif /* _FLOAT_H___ */
    239