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/* Copyright (C) 1997,1998,1999,2000,2001 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _FENV_H
# error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
#endif
/* Define bits representing the exception. We use the bit positions
of the appropriate bits in the FPU control word. */
enum
{
FE_INVALID = 0x01,
#define FE_INVALID FE_INVALID
__FE_DENORM = 0x02,
FE_DIVBYZERO = 0x04,
#define FE_DIVBYZERO FE_DIVBYZERO
FE_OVERFLOW = 0x08,
#define FE_OVERFLOW FE_OVERFLOW
FE_UNDERFLOW = 0x10,
#define FE_UNDERFLOW FE_UNDERFLOW
FE_INEXACT = 0x20
#define FE_INEXACT FE_INEXACT
};
#define FE_ALL_EXCEPT \
(FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
/* The ix87 FPU supports all of the four defined rounding modes. We
use again the bit positions in the FPU control word as the values
for the appropriate macros. */
enum
{
FE_TONEAREST = 0,
#define FE_TONEAREST FE_TONEAREST
FE_DOWNWARD = 0x400,
#define FE_DOWNWARD FE_DOWNWARD
FE_UPWARD = 0x800,
#define FE_UPWARD FE_UPWARD
FE_TOWARDZERO = 0xc00
#define FE_TOWARDZERO FE_TOWARDZERO
};
/* Type representing exception flags. */
typedef unsigned short int fexcept_t;
/* Type representing floating-point environment. This structure
corresponds to the layout of the block written by the `fstenv'
instruction and has additional fields for the contents of the MXCSR
register as written by the `stmxcsr' instruction. */
typedef struct
{
unsigned short int __control_word;
unsigned short int __unused1;
unsigned short int __status_word;
unsigned short int __unused2;
unsigned short int __tags;
unsigned short int __unused3;
unsigned int __eip;
unsigned short int __cs_selector;
unsigned int __opcode:11;
unsigned int __unused4:5;
unsigned int __data_offset;
unsigned short int __data_selector;
unsigned short int __unused5;
unsigned int __mxcsr;
}
fenv_t;
/* If the default argument is used we use this value. */
#define FE_DFL_ENV ((__const fenv_t *) -1)
#ifdef __USE_GNU
/* Floating-point environment where none of the exception is masked. */
# define FE_NOMASK_ENV ((__const fenv_t *) -2)
#endif
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