1234285Sdim/*- 2234285Sdim * Copyright (c) 1992, 1993 3234285Sdim * The Regents of the University of California. All rights reserved. 4234285Sdim * 5234285Sdim * This software was developed by the Computer Systems Engineering group 6234285Sdim * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 7234285Sdim * contributed to Berkeley. 8234285Sdim * 9234285Sdim * All advertising materials mentioning features or use of this software 10234285Sdim * must display the following acknowledgement: 11234285Sdim * This product includes software developed by the University of 12234285Sdim * California, Lawrence Berkeley Laboratory. 13234285Sdim * 14249423Sdim * Redistribution and use in source and binary forms, with or without 15234285Sdim * modification, are permitted provided that the following conditions 16234285Sdim * are met: 17234285Sdim * 1. Redistributions of source code must retain the above copyright 18234285Sdim * notice, this list of conditions and the following disclaimer. 19234285Sdim * 2. Redistributions in binary form must reproduce the above copyright 20234285Sdim * notice, this list of conditions and the following disclaimer in the 21249423Sdim * documentation and/or other materials provided with the distribution. 22234285Sdim * 4. Neither the name of the University nor the names of its contributors 23234285Sdim * may be used to endorse or promote products derived from this software 24249423Sdim * without specific prior written permission. 25234285Sdim * 26234285Sdim * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27234285Sdim * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28249423Sdim * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29249423Sdim * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30249423Sdim * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31234285Sdim * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32249423Sdim * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33234285Sdim * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34234285Sdim * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35234285Sdim * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36234285Sdim * SUCH DAMAGE. 37234285Sdim * 38234285Sdim * @(#)ieee.h 8.1 (Berkeley) 6/11/93 39234285Sdim * from: NetBSD: ieee.h,v 1.1.1.1 1998/06/20 04:58:51 eeh Exp 40234285Sdim * $FreeBSD$ 41234285Sdim */ 42234285Sdim 43234285Sdim#ifndef _MACHINE_IEEE_H_ 44234285Sdim#define _MACHINE_IEEE_H_ 45234285Sdim 46234285Sdim/* 47234285Sdim * ieee.h defines the machine-dependent layout of the machine's IEEE 48234285Sdim * floating point. It does *not* define (yet?) any of the rounding 49234285Sdim * mode bits, exceptions, and so forth. 50234285Sdim */ 51234285Sdim 52234285Sdim/* 53234285Sdim * Define the number of bits in each fraction and exponent. 54234285Sdim * 55234285Sdim * k k+1 56234285Sdim * Note that 1.0 x 2 == 0.1 x 2 and that denorms are represented 57234285Sdim * 58234285Sdim * (-exp_bias+1) 59234285Sdim * as fractions that look like 0.fffff x 2 . This means that 60234285Sdim * 61234285Sdim * -126 62234285Sdim * the number 0.10000 x 2 , for instance, is the same as the normalized 63234285Sdim * 64234285Sdim * -127 -128 65234285Sdim * float 1.0 x 2 . Thus, to represent 2 , we need one leading zero 66234285Sdim * 67234285Sdim * -129 68234285Sdim * in the fraction; to represent 2 , we need two, and so on. This 69234285Sdim * 70234285Sdim * (-exp_bias-fracbits+1) 71234285Sdim * implies that the smallest denormalized number is 2 72234285Sdim * 73234285Sdim * for whichever format we are talking about: for single precision, for 74234285Sdim * 75234285Sdim * -126 -149 76234285Sdim * instance, we get .00000000000000000000001 x 2 , or 1.0 x 2 , and 77234285Sdim * 78234285Sdim * -149 == -127 - 23 + 1. 79234285Sdim */ 80234285Sdim#define SNG_EXPBITS 8 81234285Sdim#define SNG_FRACBITS 23 82234285Sdim 83234285Sdim#define DBL_EXPBITS 11 84234285Sdim#define DBL_FRACBITS 52 85234285Sdim 86234285Sdim#ifdef notyet 87234285Sdim#define E80_EXPBITS 15 88234285Sdim#define E80_FRACBITS 64 89234285Sdim#endif 90234285Sdim 91234285Sdim#define EXT_EXPBITS 15 92234285Sdim#define EXT_FRACBITS 112 93234285Sdim 94234285Sdimstruct ieee_single { 95234285Sdim u_int sng_sign:1; 96234285Sdim u_int sng_exp:8; 97234285Sdim u_int sng_frac:23; 98234285Sdim}; 99234285Sdim 100234285Sdimstruct ieee_double { 101234285Sdim u_int dbl_sign:1; 102234285Sdim u_int dbl_exp:11; 103234285Sdim u_int dbl_frach:20; 104234285Sdim u_int dbl_fracl; 105234285Sdim}; 106234285Sdim 107234285Sdimstruct ieee_ext { 108234285Sdim u_int ext_sign:1; 109234285Sdim u_int ext_exp:15; 110234285Sdim u_int ext_frach:16; 111234285Sdim u_int ext_frachm; 112234285Sdim u_int ext_fraclm; 113234285Sdim u_int ext_fracl; 114234285Sdim}; 115234285Sdim 116234285Sdim/* 117234285Sdim * Floats whose exponent is in [1..INFNAN) (of whatever type) are 118234285Sdim * `normal'. Floats whose exponent is INFNAN are either Inf or NaN. 119234285Sdim * Floats whose exponent is zero are either zero (iff all fraction 120234285Sdim * bits are zero) or subnormal values. 121234285Sdim * 122234285Sdim * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its 123234285Sdim * high fraction; if the bit is set, it is a `quiet NaN'. 124234285Sdim */ 125234285Sdim#define SNG_EXP_INFNAN 255 126234285Sdim#define DBL_EXP_INFNAN 2047 127234285Sdim#define EXT_EXP_INFNAN 32767 128234285Sdim 129234285Sdim#if 0 130234285Sdim#define SNG_QUIETNAN (1 << 22) 131234285Sdim#define DBL_QUIETNAN (1 << 19) 132234285Sdim#define EXT_QUIETNAN (1 << 15) 133234285Sdim#endif 134234285Sdim 135234285Sdim/* 136234285Sdim * Exponent biases. 137234285Sdim */ 138234285Sdim#define SNG_EXP_BIAS 127 139234285Sdim#define DBL_EXP_BIAS 1023 140234285Sdim#define EXT_EXP_BIAS 16383 141234285Sdim 142234285Sdim#endif 143234285Sdim