Home | History | Annotate | Line # | Download | only in include
fenv.h revision 1.1.4.2
      1  1.1.4.2  uebayasi /*	$NetBSD: fenv.h,v 1.1.4.2 2010/08/17 06:44:37 uebayasi Exp $	*/
      2  1.1.4.2  uebayasi /*-
      3  1.1.4.2  uebayasi  * Copyright (c) 2004-2005 David Schultz <das (at) FreeBSD.ORG>
      4  1.1.4.2  uebayasi  * All rights reserved.
      5  1.1.4.2  uebayasi  *
      6  1.1.4.2  uebayasi  * Redistribution and use in source and binary forms, with or without
      7  1.1.4.2  uebayasi  * modification, are permitted provided that the following conditions
      8  1.1.4.2  uebayasi  * are met:
      9  1.1.4.2  uebayasi  * 1. Redistributions of source code must retain the above copyright
     10  1.1.4.2  uebayasi  *    notice, this list of conditions and the following disclaimer.
     11  1.1.4.2  uebayasi  * 2. Redistributions in binary form must reproduce the above copyright
     12  1.1.4.2  uebayasi  *    notice, this list of conditions and the following disclaimer in the
     13  1.1.4.2  uebayasi  *    documentation and/or other materials provided with the distribution.
     14  1.1.4.2  uebayasi  *
     15  1.1.4.2  uebayasi  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     16  1.1.4.2  uebayasi  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17  1.1.4.2  uebayasi  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     18  1.1.4.2  uebayasi  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     19  1.1.4.2  uebayasi  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     20  1.1.4.2  uebayasi  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     21  1.1.4.2  uebayasi  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     22  1.1.4.2  uebayasi  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     23  1.1.4.2  uebayasi  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     24  1.1.4.2  uebayasi  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     25  1.1.4.2  uebayasi  * SUCH DAMAGE.
     26  1.1.4.2  uebayasi  */
     27  1.1.4.2  uebayasi 
     28  1.1.4.2  uebayasi #ifndef	_X86_FENV_H_
     29  1.1.4.2  uebayasi #define	_X86_FENV_H_
     30  1.1.4.2  uebayasi 
     31  1.1.4.2  uebayasi #include <sys/stdint.h>
     32  1.1.4.2  uebayasi #include <i386/npx.h>
     33  1.1.4.2  uebayasi 
     34  1.1.4.2  uebayasi /*
     35  1.1.4.2  uebayasi  * Each symbol representing a floating point exception expands to an integer
     36  1.1.4.2  uebayasi  * constant expression with values, such that bitwise-inclusive ORs of _all
     37  1.1.4.2  uebayasi  * combinations_ of the constants result in distinct values.
     38  1.1.4.2  uebayasi  *
     39  1.1.4.2  uebayasi  * We use such values that allow direct bitwise operations on FPU/SSE registers.
     40  1.1.4.2  uebayasi  */
     41  1.1.4.2  uebayasi #define	FE_INVALID	0x01	/* 000000000001 */
     42  1.1.4.2  uebayasi #define	FE_DENORMAL	0x02	/* 000000000010 */
     43  1.1.4.2  uebayasi #define	FE_DIVBYZERO	0x04	/* 000000000100 */
     44  1.1.4.2  uebayasi #define	FE_OVERFLOW	0x08	/* 000000001000 */
     45  1.1.4.2  uebayasi #define	FE_UNDERFLOW	0x10	/* 000000010000 */
     46  1.1.4.2  uebayasi #define	FE_INEXACT	0x20	/* 000000100000 */
     47  1.1.4.2  uebayasi 
     48  1.1.4.2  uebayasi /*
     49  1.1.4.2  uebayasi  * The following symbol is simply the bitwise-inclusive OR of all floating-point
     50  1.1.4.2  uebayasi  * exception constants defined above.
     51  1.1.4.2  uebayasi  */
     52  1.1.4.2  uebayasi #define FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT | \
     53  1.1.4.2  uebayasi 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
     54  1.1.4.2  uebayasi 
     55  1.1.4.2  uebayasi /*
     56  1.1.4.2  uebayasi  * Each symbol representing the rounding direction, expands to an integer
     57  1.1.4.2  uebayasi  * constant expression whose value is distinct non-negative value.
     58  1.1.4.2  uebayasi  *
     59  1.1.4.2  uebayasi  * We use such values that allow direct bitwise operations on FPU/SSE registers.
     60  1.1.4.2  uebayasi  */
     61  1.1.4.2  uebayasi #define	FE_TONEAREST	0x000	/* 000000000000 */
     62  1.1.4.2  uebayasi #define	FE_DOWNWARD	0x400	/* 010000000000 */
     63  1.1.4.2  uebayasi #define	FE_UPWARD	0x800	/* 100000000000 */
     64  1.1.4.2  uebayasi #define	FE_TOWARDZERO	0xC00	/* 110000000000 */
     65  1.1.4.2  uebayasi 
     66  1.1.4.2  uebayasi /*
     67  1.1.4.2  uebayasi  * As compared to the x87 control word, the SSE unit's control has the rounding
     68  1.1.4.2  uebayasi  * control bits offset by 3 and the exception mask bits offset by 7
     69  1.1.4.2  uebayasi  */
     70  1.1.4.2  uebayasi #define	__X87_ROUND_MASK	0xC00		/* 110000000000 */
     71  1.1.4.2  uebayasi #define	__SSE_ROUND_SHIFT	3
     72  1.1.4.2  uebayasi #define	__SSE_EMASK_SHIFT	7
     73  1.1.4.2  uebayasi 
     74  1.1.4.2  uebayasi /*
     75  1.1.4.2  uebayasi  * fenv_t represents the entire floating-point environment
     76  1.1.4.2  uebayasi  */
     77  1.1.4.2  uebayasi typedef struct {
     78  1.1.4.2  uebayasi 	struct {
     79  1.1.4.2  uebayasi 		uint16_t control;	/* Control word register */
     80  1.1.4.2  uebayasi 		uint16_t unused1;
     81  1.1.4.2  uebayasi 		uint16_t status;	/* Status word register */
     82  1.1.4.2  uebayasi 		uint16_t unused2;
     83  1.1.4.2  uebayasi 		uint16_t tag;		/* Tag word register */
     84  1.1.4.2  uebayasi 		uint16_t unused3;
     85  1.1.4.2  uebayasi 		uint32_t others[4];	/* EIP, Pointer Selector, etc */
     86  1.1.4.2  uebayasi 	} x87;
     87  1.1.4.2  uebayasi 
     88  1.1.4.2  uebayasi 	uint32_t mxcsr;			/* Control and status register */
     89  1.1.4.2  uebayasi } fenv_t;
     90  1.1.4.2  uebayasi 
     91  1.1.4.2  uebayasi /*
     92  1.1.4.2  uebayasi  * The following constant represents the default floating-point environment
     93  1.1.4.2  uebayasi  * (that is, the one installed at program startup) and has type pointer to
     94  1.1.4.2  uebayasi  * const-qualified fenv_t.
     95  1.1.4.2  uebayasi  *
     96  1.1.4.2  uebayasi  * It can be used as an argument to the functions within the <fenv.h> header
     97  1.1.4.2  uebayasi  * that manage the floating-point environment.
     98  1.1.4.2  uebayasi  */
     99  1.1.4.2  uebayasi extern  fenv_t		__fe_dfl_env;
    100  1.1.4.2  uebayasi #define FE_DFL_ENV      ((const fenv_t *) &__fe_dfl_env)
    101  1.1.4.2  uebayasi 
    102  1.1.4.2  uebayasi /*
    103  1.1.4.2  uebayasi  * fexcept_t represents the floating-point status flags collectively, including
    104  1.1.4.2  uebayasi  * any status the implementation associates with the flags.
    105  1.1.4.2  uebayasi  *
    106  1.1.4.2  uebayasi  * A floating-point status flag is a system variable whose value is set (but
    107  1.1.4.2  uebayasi  * never cleared) when a floating-point exception is raised, which occurs as a
    108  1.1.4.2  uebayasi  * side effect of exceptional floating-point arithmetic to provide auxiliary
    109  1.1.4.2  uebayasi  * information.
    110  1.1.4.2  uebayasi  *
    111  1.1.4.2  uebayasi  * A floating-point control mode is a system variable whose value may be set by
    112  1.1.4.2  uebayasi  * the user to affect the subsequent behavior of floating-point arithmetic.
    113  1.1.4.2  uebayasi  */
    114  1.1.4.2  uebayasi typedef uint32_t fexcept_t;
    115  1.1.4.2  uebayasi 
    116  1.1.4.2  uebayasi #endif	/* ! _X86_FENV_H_ */
    117