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      1 /* Copyright (C) 2002, 2007, 2008, 2009, 2010 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 #if defined (__STDC_VERSION__) && __STDC_VERSION__ > 199901L
    161 /* Versions of DECIMAL_DIG for each floating-point type.  */
    162 #undef FLT_DECIMAL_DIG
    163 #undef DBL_DECIMAL_DIG
    164 #undef LDBL_DECIMAL_DIG
    165 #define FLT_DECIMAL_DIG		__FLT_DECIMAL_DIG__
    166 #define DBL_DECIMAL_DIG		__DBL_DECIMAL_DIG__
    167 #define LDBL_DECIMAL_DIG	__DECIMAL_DIG__
    168 
    169 /* Whether types support subnormal numbers.  */
    170 #undef FLT_HAS_SUBNORM
    171 #undef DBL_HAS_SUBNORM
    172 #undef LDBL_HAS_SUBNORM
    173 #define FLT_HAS_SUBNORM		__FLT_HAS_DENORM__
    174 #define DBL_HAS_SUBNORM		__DBL_HAS_DENORM__
    175 #define LDBL_HAS_SUBNORM	__LDBL_HAS_DENORM__
    176 
    177 /* Minimum positive values, including subnormals.  */
    178 #undef FLT_TRUE_MIN
    179 #undef DBL_TRUE_MIN
    180 #undef LDBL_TRUE_MIN
    181 #if __FLT_HAS_DENORM__
    182 #define FLT_TRUE_MIN	__FLT_DENORM_MIN__
    183 #else
    184 #define FLT_TRUE_MIN	__FLT_MIN__
    185 #endif
    186 #if __DBL_HAS_DENORM__
    187 #define DBL_TRUE_MIN	__DBL_DENORM_MIN__
    188 #else
    189 #define DBL_TRUE_MIN	__DBL_MIN__
    190 #endif
    191 #if __LDBL_HAS_DENORM__
    192 #define LDBL_TRUE_MIN	__LDBL_DENORM_MIN__
    193 #else
    194 #define LDBL_TRUE_MIN	__LDBL_MIN__
    195 #endif
    196 
    197 #endif /* C1X */
    198 
    199 #ifdef __STDC_WANT_DEC_FP__
    200 /* Draft Technical Report 24732, extension for decimal floating-point
    201    arithmetic: Characteristic of decimal floating types <float.h>.  */
    202 
    203 /* Number of base-FLT_RADIX digits in the significand, p.  */
    204 #undef DEC32_MANT_DIG
    205 #undef DEC64_MANT_DIG
    206 #undef DEC128_MANT_DIG
    207 #define DEC32_MANT_DIG	__DEC32_MANT_DIG__
    208 #define DEC64_MANT_DIG	__DEC64_MANT_DIG__
    209 #define DEC128_MANT_DIG	__DEC128_MANT_DIG__
    210 
    211 /* Minimum exponent. */
    212 #undef DEC32_MIN_EXP
    213 #undef DEC64_MIN_EXP
    214 #undef DEC128_MIN_EXP
    215 #define DEC32_MIN_EXP	__DEC32_MIN_EXP__
    216 #define DEC64_MIN_EXP	__DEC64_MIN_EXP__
    217 #define DEC128_MIN_EXP	__DEC128_MIN_EXP__
    218 
    219 /* Maximum exponent. */
    220 #undef DEC32_MAX_EXP
    221 #undef DEC64_MAX_EXP
    222 #undef DEC128_MAX_EXP
    223 #define DEC32_MAX_EXP	__DEC32_MAX_EXP__
    224 #define DEC64_MAX_EXP	__DEC64_MAX_EXP__
    225 #define DEC128_MAX_EXP	__DEC128_MAX_EXP__
    226 
    227 /* Maximum representable finite decimal floating-point number
    228    (there are 6, 15, and 33 9s after the decimal points respectively). */
    229 #undef DEC32_MAX
    230 #undef DEC64_MAX
    231 #undef DEC128_MAX
    232 #define DEC32_MAX   __DEC32_MAX__
    233 #define DEC64_MAX   __DEC64_MAX__
    234 #define DEC128_MAX  __DEC128_MAX__
    235 
    236 /* The difference between 1 and the least value greater than 1 that is
    237    representable in the given floating point type. */
    238 #undef DEC32_EPSILON
    239 #undef DEC64_EPSILON
    240 #undef DEC128_EPSILON
    241 #define DEC32_EPSILON	__DEC32_EPSILON__
    242 #define DEC64_EPSILON	__DEC64_EPSILON__
    243 #define DEC128_EPSILON	__DEC128_EPSILON__
    244 
    245 /* Minimum normalized positive floating-point number. */
    246 #undef DEC32_MIN
    247 #undef DEC64_MIN
    248 #undef DEC128_MIN
    249 #define DEC32_MIN	__DEC32_MIN__
    250 #define DEC64_MIN	__DEC64_MIN__
    251 #define DEC128_MIN	__DEC128_MIN__
    252 
    253 /* Minimum subnormal positive floating-point number. */
    254 #undef DEC32_SUBNORMAL_MIN
    255 #undef DEC64_SUBNORMAL_MIN
    256 #undef DEC128_SUBNORMAL_MIN
    257 #define DEC32_SUBNORMAL_MIN       __DEC32_SUBNORMAL_MIN__
    258 #define DEC64_SUBNORMAL_MIN       __DEC64_SUBNORMAL_MIN__
    259 #define DEC128_SUBNORMAL_MIN      __DEC128_SUBNORMAL_MIN__
    260 
    261 /* The floating-point expression evaluation method.
    262          -1  indeterminate
    263          0  evaluate all operations and constants just to the range and
    264             precision of the type
    265          1  evaluate operations and constants of type _Decimal32
    266 	    and _Decimal64 to the range and precision of the _Decimal64
    267             type, evaluate _Decimal128 operations and constants to the
    268 	    range and precision of the _Decimal128 type;
    269 	 2  evaluate all operations and constants to the range and
    270 	    precision of the _Decimal128 type.  */
    271 
    272 #undef DEC_EVAL_METHOD
    273 #define DEC_EVAL_METHOD	__DEC_EVAL_METHOD__
    274 
    275 #endif /* __STDC_WANT_DEC_FP__ */
    276 
    277 #endif /* _FLOAT_H___ */
    278