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/* $OpenBSD: fenv.h,v 1.2 2011/04/28 17:34:23 martynas Exp $ */
/* $NetBSD: fenv.h,v 1.1.6.2 2010/10/24 22:48:02 jym Exp $ */
/*-
* Copyright (c) 2004-2005 David Schultz <das (at) 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.
*/
#ifndef _I386_FENV_H_
#define _I386_FENV_H_
/*
* Each symbol representing a floating point exception expands to an integer
* constant expression with values, such that bitwise-inclusive ORs of _all
* combinations_ of the constants result in distinct values.
*
* We use such values that allow direct bitwise operations on FPU/SSE registers.
*/
#define FE_INVALID 0x01
#define FE_DENORMAL 0x02
#define FE_DIVBYZERO 0x04
#define FE_OVERFLOW 0x08
#define FE_UNDERFLOW 0x10
#define FE_INEXACT 0x20
/*
* The following symbol is simply the bitwise-inclusive OR of all floating-point
* exception constants defined above.
*/
#define FE_ALL_EXCEPT (FE_INVALID | FE_DENORMAL | FE_DIVBYZERO | \
FE_OVERFLOW | FE_UNDERFLOW | FE_INEXACT)
#define _SSE_MASK_SHIFT 7
/*
* Each symbol representing the rounding direction, expands to an integer
* constant expression whose value is distinct non-negative value.
*
* We use such values that allow direct bitwise operations on FPU/SSE registers.
*/
#define FE_TONEAREST 0x000
#define FE_DOWNWARD 0x400
#define FE_UPWARD 0x800
#define FE_TOWARDZERO 0xc00
/*
* The following symbol is simply the bitwise-inclusive OR of all floating-point
* rounding direction constants defined above.
*/
#define _X87_ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | FE_UPWARD | \
FE_TOWARDZERO)
#define _SSE_ROUND_SHIFT 3
/*
* fenv_t represents the entire floating-point environment.
*/
typedef struct {
struct {
unsigned int __control; /* Control word register */
unsigned int __status; /* Status word register */
unsigned int __tag; /* Tag word register */
unsigned int __others[4]; /* EIP, Pointer Selector, etc */
} __x87;
unsigned int __mxcsr; /* Control, status register */
} fenv_t;
/*
* The following constant represents the default floating-point environment
* (that is, the one installed at program startup) and has type pointer to
* const-qualified fenv_t.
*
* It can be used as an argument to the functions within the <fenv.h> header
* that manage the floating-point environment, namely fesetenv() and
* feupdateenv().
*/
extern fenv_t __fe_dfl_env;
#define FE_DFL_ENV ((const fenv_t *)&__fe_dfl_env)
/*
* fexcept_t represents the floating-point status flags collectively, including
* any status the implementation associates with the flags.
*
* A floating-point status flag is a system variable whose value is set (but
* never cleared) when a floating-point exception is raised, which occurs as a
* side effect of exceptional floating-point arithmetic to provide auxiliary
* information.
*
* A floating-point control mode is a system variable whose value may be set by
* the user to affect the subsequent behavior of floating-point arithmetic.
*/
typedef unsigned int fexcept_t;
#endif /* !_I386_FENV_H_ */
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