1
0
Fork 0
mirror of https://gitlab.com/sortix/sortix.git synced 2023-02-13 20:55:38 -05:00
sortix--sortix/libm/arch/i387/machine/fenv.h
Jonas 'Sortie' Termansen 5980be9b3c Add Sortix Math Library.
This work is based in part on code from NetBSD libm, libc and kernel.

The library is partly public domain and partly BSD-style licensed.
2013-12-17 14:30:39 +01:00

116 lines
4.4 KiB
C

/* $NetBSD: fenv.h,v 1.1 2010/07/31 21:47:54 joerg 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 INCLUDE_MACHINE_FENV_H
#define INCLUDE_MACHINE_FENV_H
#include <__/stdint.h>
#include <machine/npx.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 /* 000000000001 */
#define FE_DENORMAL 0x02 /* 000000000010 */
#define FE_DIVBYZERO 0x04 /* 000000000100 */
#define FE_OVERFLOW 0x08 /* 000000001000 */
#define FE_UNDERFLOW 0x10 /* 000000010000 */
#define FE_INEXACT 0x20 /* 000000100000 */
/*
* The following symbol is simply the bitwise-inclusive OR of all floating-point
* exception constants defined above.
*/
#define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT | \
FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
/*
* 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 /* 000000000000 */
#define FE_DOWNWARD 0x400 /* 010000000000 */
#define FE_UPWARD 0x800 /* 100000000000 */
#define FE_TOWARDZERO 0xC00 /* 110000000000 */
/*
* As compared to the x87 control word, the SSE unit's control has the rounding
* control bits offset by 3 and the exception mask bits offset by 7
*/
#define __X87_ROUND_MASK 0xC00 /* 110000000000 */
#define __SSE_ROUND_SHIFT 3
#define __SSE_EMASK_SHIFT 7
/*
* fenv_t represents the entire floating-point environment
*/
typedef struct {
struct {
__uint16_t control; /* Control word register */
__uint16_t unused1;
__uint16_t status; /* Status word register */
__uint16_t unused2;
__uint16_t tag; /* Tag word register */
__uint16_t unused3;
__uint32_t others[4]; /* EIP, Pointer Selector, etc */
} x87;
__uint32_t mxcsr; /* Control and 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.
*/
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 __uint32_t fexcept_t;
#endif /* !INCLUDE_MACHINE_FENV_H */