1405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* $OpenBSD: ieee.h,v 1.4 2010/01/23 19:11:21 miod Exp $ */ 2405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 3405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* 4405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Copyright (c) 1992, 1993 5405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * The Regents of the University of California. All rights reserved. 6405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 7405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * This software was developed by the Computer Systems Engineering group 8405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * contributed to Berkeley. 10405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 11405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * All advertising materials mentioning features or use of this software 12405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * must display the following acknowledgement: 13405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * This product includes software developed by the University of 14405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * California, Lawrence Berkeley Laboratory. 15405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 16405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Redistribution and use in source and binary forms, with or without 17405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * modification, are permitted provided that the following conditions 18405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * are met: 19405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 1. Redistributions of source code must retain the above copyright 20405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * notice, this list of conditions and the following disclaimer. 21405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 2. Redistributions in binary form must reproduce the above copyright 22405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * notice, this list of conditions and the following disclaimer in the 23405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * documentation and/or other materials provided with the distribution. 24405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 3. Neither the name of the University nor the names of its contributors 25405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * may be used to endorse or promote products derived from this software 26405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * without specific prior written permission. 27405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 28405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * SUCH DAMAGE. 39405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 40405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * @(#)ieee.h 8.1 (Berkeley) 6/11/93 41405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 42405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 43405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* 44405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * ieee.h defines the machine-dependent layout of the machine's IEEE 45405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * floating point. It does *not* define (yet?) any of the rounding 46405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * mode bits, exceptions, and so forth. 47405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 48405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 49405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* 50405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Define the number of bits in each fraction and exponent. 51405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 52405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * k k+1 53405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Note that 1.0 x 2 == 0.1 x 2 and that denorms are represented 54405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 55405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * (-exp_bias+1) 56405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * as fractions that look like 0.fffff x 2 . This means that 57405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 58405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * -126 59405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * the number 0.10000 x 2 , for instance, is the same as the normalized 60405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 61405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * -127 -128 62405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * float 1.0 x 2 . Thus, to represent 2 , we need one leading zero 63405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 64405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * -129 65405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * in the fraction; to represent 2 , we need two, and so on. This 66405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 67405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * (-exp_bias-fracbits+1) 68405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * implies that the smallest denormalized number is 2 69405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 70405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * for whichever format we are talking about: for single precision, for 71405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 72405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * -126 -149 73405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * instance, we get .00000000000000000000001 x 2 , or 1.0 x 2 , and 74405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 75405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * -149 == -127 - 23 + 1. 76405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 77405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define SNG_EXPBITS 8 78405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define SNG_FRACBITS 23 79405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 80405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_EXPBITS 11 81405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_FRACHBITS 20 82405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_FRACLBITS 32 83405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_FRACBITS 52 84405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 85405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_EXPBITS 15 86405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_FRACHBITS 16 87405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_FRACHMBITS 32 88405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_FRACLMBITS 32 89405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_FRACLBITS 32 90405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_FRACBITS 112 91405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 92405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_IMPLICIT_NBIT 93405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 94405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_TO_ARRAY32(p, a) do { \ 95405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham (a)[0] = (uint32_t)(p)->ext_fracl; \ 96405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham (a)[1] = (uint32_t)(p)->ext_fraclm; \ 97405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham (a)[2] = (uint32_t)(p)->ext_frachm; \ 98405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham (a)[3] = (uint32_t)(p)->ext_frach; \ 99405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham} while(0) 100405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 101405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamstruct ieee_single { 102405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#ifdef __MIPSEB__ 103405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int sng_sign:1; 104405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int sng_exp:8; 105405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int sng_frac:23; 106405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#else 107405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int sng_frac:23; 108405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int sng_exp:8; 109405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int sng_sign:1; 110405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#endif 111405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham}; 112405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 113405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamstruct ieee_double { 114405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#ifdef __MIPSEB__ 115405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_sign:1; 116405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_exp:11; 117405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_frach:20; 118405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_fracl; 119405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#else 120405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_fracl; 121405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_frach:20; 122405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_exp:11; 123405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int dbl_sign:1; 124405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#endif 125405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham}; 126405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 127405b8029a6888f386adf3512113a33546141d1c8Raghu Gandhamstruct ieee_ext { 128405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#ifdef __MIPSEB__ 129405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_sign:1; 130405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_exp:15; 131405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_frach:16; 132405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_frachm; 133405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_fraclm; 134405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_fracl; 135405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#else 136405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_fracl; 137405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_fraclm; 138405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_frachm; 139405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_frach:16; 140405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_exp:15; 141405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham u_int ext_sign:1; 142405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#endif 143405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham}; 144405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 145405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* 146405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Floats whose exponent is in [1..INFNAN) (of whatever type) are 147405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * `normal'. Floats whose exponent is INFNAN are either Inf or NaN. 148405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Floats whose exponent is zero are either zero (iff all fraction 149405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * bits are zero) or subnormal values. 150405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * 151405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its 152405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * high fraction; if the bit is set, it is a `quiet NaN'. 153405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 154405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define SNG_EXP_INFNAN 255 155405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_EXP_INFNAN 2047 156405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_EXP_INFNAN 32767 157405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 158405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#if 0 159405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define SNG_QUIETNAN (1 << 22) 160405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_QUIETNAN (1 << 19) 161405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_QUIETNAN (1 << 15) 162405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#endif 163405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham 164405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham/* 165405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham * Exponent biases. 166405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham */ 167405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define SNG_EXP_BIAS 127 168405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define DBL_EXP_BIAS 1023 169405b8029a6888f386adf3512113a33546141d1c8Raghu Gandham#define EXT_EXP_BIAS 16383 170