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/* Copyright (C) 1997, 1998 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. 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 FPSCR... */
enum
{
FE_INEXACT = 1 << (31 - 6),
#define FE_INEXACT FE_INEXACT
FE_DIVBYZERO = 1 << (31 - 5),
#define FE_DIVBYZERO FE_DIVBYZERO
FE_UNDERFLOW = 1 << (31 - 4),
#define FE_UNDERFLOW FE_UNDERFLOW
FE_OVERFLOW = 1 << (31 - 3),
#define FE_OVERFLOW FE_OVERFLOW
/* ... except for FE_INVALID, for which we use bit 31. FE_INVALID
actually corresponds to bits 7 through 12 and 21 through 23
in the FPSCR, but we can't use that because the current draft
says that it must be a power of 2. Instead we use bit 2 which
is the summary bit for all the FE_INVALID exceptions, which
kind of makes sense. */
FE_INVALID = 1 << (31 - 2),
#define FE_INVALID FE_INVALID
#ifdef __USE_GNU
/* Breakdown of the FE_INVALID bits. Setting FE_INVALID on an
input to a routine is equivalent to setting all of these bits;
FE_INVALID will be set on output from a routine iff one of
these bits is set. Note, though, that you can't disable or
enable these exceptions individually. */
/* Operation with SNaN. */
FE_INVALID_SNAN = 1 << (31 - 7),
# define FE_INVALID_SNAN FE_INVALID_SNAN
/* Inf - Inf */
FE_INVALID_ISI = 1 << (31 - 8),
# define FE_INVALID_ISI FE_INVALID_ISI
/* Inf / Inf */
FE_INVALID_IDI = 1 << (31 - 9),
# define FE_INVALID_IDI FE_INVALID_IDI
/* 0 / 0 */
FE_INVALID_ZDZ = 1 << (31 - 10),
# define FE_INVALID_ZDZ FE_INVALID_ZDZ
/* Inf * 0 */
FE_INVALID_IMZ = 1 << (31 - 11),
# define FE_INVALID_IMZ FE_INVALID_IMZ
/* Comparison with NaN or SNaN. */
FE_INVALID_COMPARE = 1 << (31 - 12),
# define FE_INVALID_COMPARE FE_INVALID_COMPARE
/* Invalid operation flag for software (not set by hardware). */
/* Note that some chips don't have this implemented, presumably
because no-one expected anyone to write software for them %-). */
FE_INVALID_SOFTWARE = 1 << (31 - 21),
# define FE_INVALID_SOFTWARE FE_INVALID_SOFTWARE
/* Square root of negative number (including -Inf). */
/* Note that some chips don't have this implemented. */
FE_INVALID_SQRT = 1 << (31 - 22),
# define FE_INVALID_SQRT FE_INVALID_SQRT
/* Conversion-to-integer of a NaN or a number too large or too small. */
FE_INVALID_INTEGER_CONVERSION = 1 << (31 - 23)
# define FE_INVALID_INTEGER_CONVERSION FE_INVALID_INTEGER_CONVERSION
# define FE_ALL_INVALID \
(FE_INVALID_SNAN | FE_INVALID_ISI | FE_INVALID_IDI | FE_INVALID_ZDZ \
| FE_INVALID_IMZ | FE_INVALID_COMPARE | FE_INVALID_SOFTWARE \
| FE_INVALID_SQRT | FE_INVALID_INTEGER_CONVERSION)
#endif
};
#define FE_ALL_EXCEPT \
(FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
/* PowerPC chips support all of the four defined rounding modes. We
use the bit pattern in the FPSCR as the values for the
appropriate macros. */
enum
{
FE_TONEAREST = 0,
#define FE_TONEAREST FE_TONEAREST
FE_TOWARDZERO = 1,
#define FE_TOWARDZERO FE_TOWARDZERO
FE_UPWARD = 2,
#define FE_UPWARD FE_UPWARD
FE_DOWNWARD = 3
#define FE_DOWNWARD FE_DOWNWARD
};
/* Type representing exception flags. */
typedef unsigned int fexcept_t;
/* Type representing floating-point environment. We leave it as 'double'
for efficiency reasons (rather than writing it to a 32-bit integer). */
typedef double fenv_t;
/* If the default argument is used we use this value. */
extern const fenv_t __fe_dfl_env;
#define FE_DFL_ENV (&__fe_dfl_env)
#ifdef __USE_GNU
/* Floating-point environment where all exceptions are enabled. Note that
this is not sufficient to give you SIGFPE. */
extern const fenv_t __fe_enabled_env;
# define FE_ENABLED_ENV (&__fe_enabled_env)
/* Floating-point environment with (processor-dependent) non-IEEE floating
point. */
extern const fenv_t __fe_nonieee_env;
# define FE_NONIEEE_ENV (&__fe_nonieee_env)
/* Floating-point environment with all exceptions enabled. Note that
just evaluating this value will set the processor into 'FPU
exceptions imprecise recoverable' mode, which may cause a significant
performance penalty (but have no other visible effect). */
extern const fenv_t *__fe_nomask_env __P ((void));
# define FE_NOMASK_ENV (__fe_nomask_env ())
#endif
#if defined __OPTIMIZE__ && !defined _SOFT_FLOAT
/* Inline definition for fegetround. */
# define fegetround() \
(__extension__ ({ int __fegetround_result; \
__asm__ ("mcrfs 7,7 ; mfcr %0" \
: "=r"(__fegetround_result) : : "cr7"); \
__fegetround_result & 3; }))
/* The weird 'i#*X' constraints on the following suppress a gcc
warning when __excepts is not a constant. Otherwise, they mean the
same as just plain 'i'. */
/* Inline definition for feraiseexcept. */
# define feraiseexcept(__excepts) \
((__builtin_constant_p (__excepts) \
&& ((__excepts) & ((__excepts)-1)) == 0 \
&& (__excepts) != FE_INVALID) \
? ((__excepts) != 0 \
? (__extension__ ({ __asm__ __volatile__ \
("mtfsb1 %s0" \
: : "i#*X"(__builtin_ffs (__excepts))); \
(void)0; })) \
: (void)0) \
: (feraiseexcept) (__excepts))
/* Inline definition for feclearexcept. */
# define feclearexcept(__excepts) \
((__builtin_constant_p (__excepts) \
&& ((__excepts) & ((__excepts)-1)) == 0 \
&& (__excepts) != FE_INVALID) \
? ((__excepts) != 0 \
? (__extension__ ({ __asm__ __volatile__ \
("mtfsb0 %s0" \
: : "i#*X"(__builtin_ffs (__excepts))); \
(void)0; })) \
: (void)0) \
: (feclearexcept) (__excepts))
#endif /* __OPTIMIZE__ && !_SOFT_FLOAT */
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