freebsd-nq/lib/msun/i387/fenv.h
David Schultz 10b01832c3 Replace fegetmask() and fesetmask() with feenableexcept(),
fedisableexcept(), and fegetexcept().  These two sets of routines
provide the same functionality.  I implemented the former as an
undocumented internal interface to make the regression test easier to
write.  However, fe(enable|disable|get)except() is already part of
glibc, and I would like to avoid gratuitous differences.  The only
major flaw in the glibc API is that there's no good way to report
errors on processors that don't support all the unmasked exceptions.
2005-03-16 19:03:46 +00:00

236 lines
5.0 KiB
C

/*-
* Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _FENV_H_
#define _FENV_H_
#include <sys/cdefs.h>
#include <sys/_types.h>
typedef struct {
__uint32_t __control;
__uint32_t __status;
__uint32_t __tag;
char __other[16];
} fenv_t;
typedef __uint16_t fexcept_t;
/* Exception flags */
#define FE_INVALID 0x01
#define FE_DENORMAL 0x02
#define FE_DIVBYZERO 0x04
#define FE_OVERFLOW 0x08
#define FE_UNDERFLOW 0x10
#define FE_INEXACT 0x20
#define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT | \
FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
/* Rounding modes */
#define FE_TONEAREST 0x0000
#define FE_DOWNWARD 0x0400
#define FE_UPWARD 0x0800
#define FE_TOWARDZERO 0x0c00
#define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \
FE_UPWARD | FE_TOWARDZERO)
__BEGIN_DECLS
/* Default floating-point environment */
extern const fenv_t __fe_dfl_env;
#define FE_DFL_ENV (&__fe_dfl_env)
#define __fldcw(__cw) __asm __volatile("fldcw %0" : : "m" (__cw))
#define __fldenv(__env) __asm __volatile("fldenv %0" : : "m" (__env))
#define __fnclex() __asm __volatile("fnclex")
#define __fnstenv(__env) __asm __volatile("fnstenv %0" : "=m" (*(__env)))
#define __fnstcw(__cw) __asm __volatile("fnstcw %0" : "=m" (*(__cw)))
#define __fnstsw(__sw) __asm __volatile("fnstsw %0" : "=am" (*(__sw)))
#define __fwait() __asm __volatile("fwait")
static __inline int
feclearexcept(int __excepts)
{
fenv_t __env;
if (__excepts == FE_ALL_EXCEPT) {
__fnclex();
} else {
__fnstenv(&__env);
__env.__status &= ~__excepts;
__fldenv(__env);
}
return (0);
}
static __inline int
fegetexceptflag(fexcept_t *__flagp, int __excepts)
{
int __status;
__fnstsw(&__status);
*__flagp = __status & __excepts;
return (0);
}
static __inline int
fesetexceptflag(const fexcept_t *__flagp, int __excepts)
{
fenv_t __env;
__fnstenv(&__env);
__env.__status &= ~__excepts;
__env.__status |= *__flagp & __excepts;
__fldenv(__env);
return (0);
}
static __inline int
feraiseexcept(int __excepts)
{
fexcept_t __ex = __excepts;
fesetexceptflag(&__ex, __excepts);
__fwait();
return (0);
}
static __inline int
fetestexcept(int __excepts)
{
int __status;
__fnstsw(&__status);
return (__status & __excepts);
}
static __inline int
fegetround(void)
{
int __control;
__fnstcw(&__control);
return (__control & _ROUND_MASK);
}
static __inline int
fesetround(int __round)
{
int __control;
if (__round & ~_ROUND_MASK)
return (-1);
__fnstcw(&__control);
__control &= ~_ROUND_MASK;
__control |= __round;
__fldcw(__control);
return (0);
}
static __inline int
fegetenv(fenv_t *__envp)
{
int __control;
/*
* fnstenv masks all exceptions, so we need to save and
* restore the control word to avoid this side effect.
*/
__fnstcw(&__control);
__fnstenv(__envp);
__fldcw(__control);
return (0);
}
static __inline int
feholdexcept(fenv_t *__envp)
{
__fnstenv(__envp);
__fnclex();
return (0);
}
static __inline int
fesetenv(const fenv_t *__envp)
{
__fldenv(*__envp);
return (0);
}
static __inline int
feupdateenv(const fenv_t *__envp)
{
int __status;
__fnstsw(&__status);
__fldenv(*__envp);
feraiseexcept(__status & FE_ALL_EXCEPT);
return (0);
}
#if __BSD_VISIBLE
static __inline int
feenableexcept(int __mask)
{
int __control;
__fnstcw(&__control);
__mask = __control & ~(__mask & FE_ALL_EXCEPT);
__fldcw(__mask);
return (~__control & FE_ALL_EXCEPT);
}
static __inline int
fedisableexcept(int __mask)
{
int __control;
__fnstcw(&__control);
__mask = __control | (__mask & FE_ALL_EXCEPT);
__fldcw(__mask);
return (~__control & FE_ALL_EXCEPT);
}
static __inline int
fegetexcept(void)
{
int __control;
__fnstcw(&__control);
return (~__control & FE_ALL_EXCEPT);
}
#endif /* __BSD_VISIBLE */
__END_DECLS
#endif /* !_FENV_H_ */