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/*        $NetBSD: ieee.h,v 1.11 2010/09/15 16:11:28 christos 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. 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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/*
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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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#include <sys/ieee754.h>
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#define        EXT_EXPBITS        15
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#define EXT_FRACHBITS        32
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#define        EXT_FRACLBITS        32
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#define        EXT_FRACBITS        (EXT_FRACLBITS + EXT_FRACHBITS)
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#define        EXT_TO_ARRAY32(u, a) do {                        \
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        (a)[0] = (uint32_t)(u).extu_ext.ext_fracl;        \
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        (a)[1] = (uint32_t)(u).extu_ext.ext_frach;        \
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} while(/*CONSTCOND*/0)
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/*
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 * struct ieee_ext is the raw storage layout of the 80-bit
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 * extended-precision type as implemented by the FPU.  Per the
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 * respective ABI specifications, it is followed by a tail padding of
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 *
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 *   amd64: 48 bits,
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 *   i386:  16 bits.
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 */
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struct ieee_ext {
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        u_int        ext_fracl:EXT_FRACLBITS;
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        u_int        ext_frach:EXT_FRACHBITS;
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#if 0
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        u_int        ext_int:1;
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#endif
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        u_int        ext_exp:EXT_EXPBITS;
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        u_int        ext_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        EXT_EXP_INFNAN        0x7fff
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#define        EXT_EXP_INF        0x7fff
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#define        EXT_EXP_NAN        0x7fff
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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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#define        EXT_QUIETNAN        (1 << 30)
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#endif
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/*
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 * Exponent biases.
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 */
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#define        EXT_EXP_BIAS        16383
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/*
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 * Convenience data structures.
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 */
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union ieee_ext_u {
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        long double                extu_ld;
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        struct ieee_ext                extu_ext;
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};
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#define extu_exp        extu_ext.ext_exp
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#define extu_sign        extu_ext.ext_sign
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#define extu_fracl        extu_ext.ext_fracl
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#define extu_frach        extu_ext.ext_frach
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#define LDBL_NBIT        0x80000000
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#define mask_nbit_l(u)        ((u).extu_frach &= ~LDBL_NBIT)