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편집 파일: ieee754.h

/* Copyright (C) 1992-2018 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 <http://www.gnu.org/licenses/>. */ #ifndef _IEEE754_H #define _IEEE754_H 1 #include <features.h> #include <endian.h> __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 # if __FLOAT_WORD_ORDER == __BIG_ENDIAN unsigned int mantissa0:20; unsigned int exponent:11; unsigned int negative:1; unsigned int mantissa1:32; # else /* Together these comprise the mantissa. */ unsigned int mantissa1:32; unsigned int mantissa0:20; unsigned int exponent:11; unsigned int negative:1; # endif #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 # if __FLOAT_WORD_ORDER == __BIG_ENDIAN unsigned int mantissa0:19; unsigned int quiet_nan:1; unsigned int exponent:11; unsigned int negative:1; 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 #endif } ieee_nan; }; #define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */ union ieee854_long_double { long double d; /* This is the IEEE 854 double-extended-precision format. */ struct { #if __BYTE_ORDER == __BIG_ENDIAN unsigned int negative:1; unsigned int exponent:15; unsigned int empty:16; unsigned int mantissa0:32; unsigned int mantissa1:32; #endif #if __BYTE_ORDER == __LITTLE_ENDIAN # if __FLOAT_WORD_ORDER == __BIG_ENDIAN unsigned int exponent:15; unsigned int negative:1; unsigned int empty:16; unsigned int mantissa0:32; unsigned int mantissa1:32; # else unsigned int mantissa1:32; unsigned int mantissa0:32; unsigned int exponent:15; unsigned int negative:1; unsigned int empty:16; # endif #endif } ieee; /* This is for NaNs in the IEEE 854 double-extended-precision format. */ struct { #if __BYTE_ORDER == __BIG_ENDIAN unsigned int negative:1; unsigned int exponent:15; unsigned int empty:16; unsigned int one:1; unsigned int quiet_nan:1; unsigned int mantissa0:30; unsigned int mantissa1:32; #endif #if __BYTE_ORDER == __LITTLE_ENDIAN # if __FLOAT_WORD_ORDER == __BIG_ENDIAN unsigned int exponent:15; unsigned int negative:1; unsigned int empty:16; unsigned int mantissa0:30; unsigned int quiet_nan:1; unsigned int one:1; unsigned int mantissa1:32; # else unsigned int mantissa1:32; unsigned int mantissa0:30; unsigned int quiet_nan:1; unsigned int one:1; unsigned int exponent:15; unsigned int negative:1; unsigned int empty:16; # endif #endif } ieee_nan; }; #define IEEE854_LONG_DOUBLE_BIAS 0x3fff __END_DECLS #endif /* ieee754.h */