Home | History | Annotate | Line # | Download | only in include
ieee.h revision 1.10 
      1 /*	$NetBSD: ieee.h,v 1.10 2014/01/31 11:53:37 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 MIPS 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	48
     64 #define	EXT_FRACLBITS	64
     65 #define	EXT_FRACBITS	(EXT_FRACLBITS + EXT_FRACHBITS)
     66 
     67 #define	EXT_TO_ARRAY32(u, a) do {				\
     68 	(a)[0] = (uint32_t)((u).extu_ext.ext_fracl >>  0);	\
     69 	(a)[1] = (uint32_t)((u).extu_ext.ext_fracl >> 32);	\
     70 	(a)[2] = (uint32_t)((u).extu_ext.ext_frach >>  0);	\
     71 	(a)[3] = (uint32_t)((u).extu_ext.ext_frach >> 32);	\
     72 } while(/*CONSTCOND*/0)
     73 
     74 struct ieee_ext {
     75 #if _BYTE_ORDER == _BIG_ENDIAN
     76 	uint64_t ext_sign:1;
     77 	uint64_t ext_exp:EXT_EXPBITS;
     78 	uint64_t ext_frach:EXT_FRACHBITS;
     79 	uint64_t ext_fracl;
     80 #else
     81 	uint64_t ext_fracl;
     82 	uint64_t ext_frach:EXT_FRACHBITS;
     83 	uint64_t ext_exp:EXT_EXPBITS;
     84 	uint64_t ext_sign:1;
     85 #endif
     86 };
     87 
     88 /*
     89  * Floats whose exponent is in [1..INFNAN) (of whatever type) are
     90  * `normal'.  Floats whose exponent is INFNAN are either Inf or NaN.
     91  * Floats whose exponent is zero are either zero (iff all fraction
     92  * bits are zero) or subnormal values.
     93  *
     94  * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its
     95  * high fraction; if the bit is set, it is a `quiet NaN'.
     96  */
     97 #define	EXT_EXP_INFNAN	0x7fff
     98 #define	EXT_EXP_INF	0x7fff
     99 #define	EXT_EXP_NAN	0x7fff
    100 
    101 #if 0
    102 #define	SNG_QUIETNAN	(1 << 22)
    103 #define	DBL_QUIETNAN	(1 << 19)
    104 #define	EXT_QUIETNAN	(1 << 15)
    105 #endif
    106 
    107 /*
    108  * Exponent biases.
    109  */
    110 #define	EXT_EXP_BIAS	16383
    111 
    112 /*
    113  * Convenience data structures.
    114  */
    115 union ieee_ext_u {
    116 	long double		extu_ld;
    117 	struct ieee_ext		extu_ext;
    118 };
    119 
    120 #define extu_exp	extu_ext.ext_exp
    121 #define extu_sign	extu_ext.ext_sign
    122 #define extu_fracl	extu_ext.ext_fracl
    123 #define extu_frach	extu_ext.ext_frach
    124 
    125 #define LDBL_IMPLICIT_NBIT	1	/* our NBIT is implicit */
    126 
    127 #endif /* __mips_n32 || __mips_n64 */
    128 
    129 #endif /* _MIPS_IEEE_H */
    130