/* Copyright (C) 1992-2016 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see . */ #ifndef _IEEE754_H #define _IEEE754_H 1 #include #include __BEGIN_DECLS union ieee754_float { float f; /* This is the IEEE 754 single-precision format. */ struct { #if __BYTE_ORDER == __BIG_ENDIAN unsigned int negative:1; unsigned int exponent:8; unsigned int mantissa:23; #endif /* Big endian. */ #if __BYTE_ORDER == __LITTLE_ENDIAN unsigned int mantissa:23; unsigned int exponent:8; unsigned int negative:1; #endif /* Little endian. */ } ieee; /* This format makes it easier to see if a NaN is a signalling NaN. */ struct { #if __BYTE_ORDER == __BIG_ENDIAN unsigned int negative:1; unsigned int exponent:8; unsigned int quiet_nan:1; unsigned int mantissa:22; #endif /* Big endian. */ #if __BYTE_ORDER == __LITTLE_ENDIAN unsigned int mantissa:22; unsigned int quiet_nan:1; unsigned int exponent:8; unsigned int negative:1; #endif /* Little endian. */ } ieee_nan; }; #define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */ union ieee754_double { double d; /* This is the IEEE 754 double-precision format. */ struct { #if __BYTE_ORDER == __BIG_ENDIAN unsigned int negative:1; unsigned int exponent:11; /* Together these comprise the mantissa. */ unsigned int mantissa0:20; unsigned int mantissa1:32; #endif /* Big endian. */ #if __BYTE_ORDER == __LITTLE_ENDIAN /* Together these comprise the mantissa. */ unsigned int mantissa1:32; unsigned int mantissa0:20; unsigned int exponent:11; unsigned int negative:1; #endif /* Little endian. */ } ieee; /* This format makes it easier to see if a NaN is a signalling NaN. */ struct { #if __BYTE_ORDER == __BIG_ENDIAN unsigned int negative:1; unsigned int exponent:11; unsigned int quiet_nan:1; /* Together these comprise the mantissa. */ unsigned int mantissa0:19; unsigned int mantissa1:32; #else /* Together these comprise the mantissa. */ unsigned int mantissa1:32; unsigned int mantissa0:19; unsigned int quiet_nan:1; unsigned int exponent:11; unsigned int negative:1; #endif } ieee_nan; }; #define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */ /* IBM extended format for long double. Each long double is made up of two IEEE doubles. The value of the long double is the sum of the values of the two parts. The most significant part is required to be the value of the long double rounded to the nearest double, as specified by IEEE. For Inf values, the least significant part is required to be one of +0.0 or -0.0. No other requirements are made; so, for example, 1.0 may be represented as (1.0, +0.0) or (1.0, -0.0), and the low part of a NaN is don't-care. */ union ibm_extended_long_double { long double ld; union ieee754_double d[2]; }; __END_DECLS #endif /* ieee754.h */