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ieee.h revision 1.6 
      1 /*	$NetBSD: ieee.h,v 1.6 2011/01/17 23:53:03 matt Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1992, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This software was developed by the Computer Systems Engineering group
      8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
      9  * contributed to Berkeley.
     10  *
     11  * All advertising materials mentioning features or use of this software
     12  * must display the following acknowledgement:
     13  *	This product includes software developed by the University of
     14  *	California, Lawrence Berkeley Laboratory.
     15  *
     16  * Redistribution and use in source and binary forms, with or without
     17  * modification, are permitted provided that the following conditions
     18  * are met:
     19  * 1. Redistributions of source code must retain the above copyright
     20  *    notice, this list of conditions and the following disclaimer.
     21  * 2. Redistributions in binary form must reproduce the above copyright
     22  *    notice, this list of conditions and the following disclaimer in the
     23  *    documentation and/or other materials provided with the distribution.
     24  * 3. Neither the name of the University nor the names of its contributors
     25  *    may be used to endorse or promote products derived from this software
     26  *    without specific prior written permission.
     27  *
     28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     38  * SUCH DAMAGE.
     39  *
     40  *	@(#)ieee.h	8.1 (Berkeley) 6/11/93
     41  */
     42 
     43 /*
     44  * ieee.h defines the machine-dependent layout of the machine's IEEE
     45  * floating point.  It does *not* define (yet?) any of the rounding
     46  * mode bits, exceptions, and so forth.
     47  */
     48 
     49 #ifndef _MIPS_IEEE_H
     50 #define _MIPS_IEEE_H
     51 
     52 #include <sys/ieee754.h>
     53 
     54 /*
     55  * The SPARC architecture defines the following IEEE 754 compliant
     56  * 128-bit extended-precision format, which is supported only by the
     57  * v9 toolchain.
     58  */
     59 
     60 #if defined(__mips_n32) || defined(__mips_n64)
     61 
     62 #define	EXT_EXPBITS	15
     63 #define EXT_FRACHBITS	16
     64 #define	EXT_FRACHMBITS	32
     65 #define	EXT_FRACLMBITS	32
     66 #define	EXT_FRACLBITS	32
     67 #define	EXT_FRACBITS	(EXT_FRACLBITS + EXT_FRACLMBITS + EXT_FRACHMBITS + EXT_FRACHBITS)
     68 
     69 #define	EXT_TO_ARRAY32(u, a) do {			\
     70 	(a)[0] = (uint32_t)(u).extu_ext.ext_fracl;	\
     71 	(a)[1] = (uint32_t)(u).extu_ext.ext_fraclm;	\
     72 	(a)[2] = (uint32_t)(u).extu_ext.ext_frachm;	\
     73 	(a)[3] = (uint32_t)(u).extu_ext.ext_frach;	\
     74 } while(/*CONSTCOND*/0)
     75 
     76 struct ieee_ext {
     77 #if _BYTE_ORDER == _BIG_ENDIAN
     78 	u_int	ext_sign:1;
     79 	u_int	ext_exp:EXT_EXPBITS;
     80 	u_int	ext_frach:EXT_FRACHBITS;
     81 	u_int	ext_frachm;
     82 	u_int	ext_fraclm;
     83 	u_int	ext_fracl;
     84 #else
     85 	u_int	ext_fracl;
     86 	u_int	ext_fraclm;
     87 	u_int	ext_frachm;
     88 	u_int	ext_frach:EXT_FRACHBITS;
     89 	u_int	ext_exp:EXT_EXPBITS;
     90 	u_int	ext_sign:1;
     91 #endif
     92 };
     93 
     94 /*
     95  * Floats whose exponent is in [1..INFNAN) (of whatever type) are
     96  * `normal'.  Floats whose exponent is INFNAN are either Inf or NaN.
     97  * Floats whose exponent is zero are either zero (iff all fraction
     98  * bits are zero) or subnormal values.
     99  *
    100  * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its
    101  * high fraction; if the bit is set, it is a `quiet NaN'.
    102  */
    103 #define	EXT_EXP_INFNAN	0x7fff
    104 #define	EXT_EXP_INF	0x7fff
    105 #define	EXT_EXP_NAN	0x7fff
    106 
    107 #if 0
    108 #define	SNG_QUIETNAN	(1 << 22)
    109 #define	DBL_QUIETNAN	(1 << 19)
    110 #define	EXT_QUIETNAN	(1 << 15)
    111 #endif
    112 
    113 /*
    114  * Exponent biases.
    115  */
    116 #define	EXT_EXP_BIAS	16383
    117 
    118 /*
    119  * Convenience data structures.
    120  */
    121 union ieee_ext_u {
    122 	long double		extu_ld;
    123 	struct ieee_ext		extu_ext;
    124 };
    125 
    126 #define extu_exp	extu_ext.ext_exp
    127 #define extu_sign	extu_ext.ext_sign
    128 #define extu_fracl	extu_ext.ext_fracl
    129 #define extu_frach	extu_ext.ext_frach
    130 
    131 #define LDBL_NBIT	0x80000000
    132 #define mask_nbit_l(u)	((u).extu_frach &= ~LDBL_NBIT)
    133 
    134 #endif /* __mips_n32 || __mips_n64 */
    135 
    136 #endif /* _MIPS_IEEE_H */
    137