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1ebcad5720
not work on any real hardware (or fully work on any simulator). Much more needs to happen before this is actually functional but its nice to see the FreeBSD copyright message appear in the ia64 simulator.
125 lines
4.2 KiB
C
125 lines
4.2 KiB
C
/* $FreeBSD$ */
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/* From: NetBSD: ieee.h,v 1.2 1997/04/06 08:47:27 cgd Exp */
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/*
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* Copyright (c) 1992, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This software was developed by the Computer Systems Engineering group
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* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
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* contributed to Berkeley.
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*
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* All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Lawrence Berkeley Laboratory.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)ieee.h 8.1 (Berkeley) 6/11/93
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*
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* from: Header: ieee.h,v 1.7 92/11/26 02:04:37 torek Exp
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*/
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/*
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* ieee.h defines the machine-dependent layout of the machine's IEEE
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* floating point. It does *not* define (yet?) any of the rounding
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* mode bits, exceptions, and so forth.
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*/
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/*
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* Define the number of bits in each fraction and exponent.
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*
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* k k+1
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* Note that 1.0 x 2 == 0.1 x 2 and that denorms are represented
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*
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* (-exp_bias+1)
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* as fractions that look like 0.fffff x 2 . This means that
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*
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* -126
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* the number 0.10000 x 2 , for instance, is the same as the normalized
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*
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* -127 -128
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* float 1.0 x 2 . Thus, to represent 2 , we need one leading zero
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*
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* -129
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* in the fraction; to represent 2 , we need two, and so on. This
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*
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* (-exp_bias-fracbits+1)
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* implies that the smallest denormalized number is 2
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*
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* for whichever format we are talking about: for single precision, for
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*
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* -126 -149
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* instance, we get .00000000000000000000001 x 2 , or 1.0 x 2 , and
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*
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* -149 == -127 - 23 + 1.
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*/
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#define SNG_EXPBITS 8
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#define SNG_FRACBITS 23
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#define DBL_EXPBITS 11
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#define DBL_FRACBITS 52
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struct ieee_single {
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u_int sng_frac:23;
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u_int sng_exp:8;
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u_int sng_sign:1;
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};
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struct ieee_double {
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u_int dbl_fracl;
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u_int dbl_frach:20;
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u_int dbl_exp:11;
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u_int dbl_sign:1;
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};
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/*
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* Floats whose exponent is in [1..INFNAN) (of whatever type) are
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* `normal'. Floats whose exponent is INFNAN are either Inf or NaN.
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* Floats whose exponent is zero are either zero (iff all fraction
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* bits are zero) or subnormal values.
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*
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* A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its
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* high fraction; if the bit is set, it is a `quiet NaN'.
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*/
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#define SNG_EXP_INFNAN 255
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#define DBL_EXP_INFNAN 2047
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#if 0
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#define SNG_QUIETNAN (1 << 22)
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#define DBL_QUIETNAN (1 << 19)
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#endif
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/*
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* Exponent biases.
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*/
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#define SNG_EXP_BIAS 127
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#define DBL_EXP_BIAS 1023
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