text: /*	$NetBSD: ieee.h,v 1.1.1.1 1998/06/20 04:58:51 eeh Exp $ */
  
  /*
   * Copyright (c) 1992, 1993
   *	The Regents of the University of California.  All rights reserved.
   *
   * This software was developed by the Computer Systems Engineering group
   * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
   * contributed to Berkeley.
   *
   * All advertising materials mentioning features or use of this software
   * must display the following acknowledgement:
   *	This product includes software developed by the University of
   *	California, Lawrence Berkeley Laboratory.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *	This product includes software developed by the University of
   *	California, Berkeley and its contributors.
   * 4. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   *	@(#)ieee.h	8.1 (Berkeley) 6/11/93
   */
  
  /*
   * ieee.h defines the machine-dependent layout of the machine's IEEE
   * floating point.  It does *not* define (yet?) any of the rounding
   * mode bits, exceptions, and so forth.
   */
  
  /*
   * Define the number of bits in each fraction and exponent.
   *
   *		     k	         k+1
   * Note that  1.0 x 2  == 0.1 x 2      and that denorms are represented
   *
   *					  (-exp_bias+1)
   * as fractions that look like 0.fffff x 2             .  This means that
   *
   *			 -126
   * the number 0.10000 x 2    , for instance, is the same as the normalized
   *
   *		-127			   -128
   * float 1.0 x 2    .  Thus, to represent 2    , we need one leading zero
   *
   *				  -129
   * in the fraction; to represent 2    , we need two, and so on.  This
   *
   *						     (-exp_bias-fracbits+1)
   * implies that the smallest denormalized number is 2
   *
   * for whichever format we are talking about: for single precision, for
   *
   *						-126		-149
   * instance, we get .00000000000000000000001 x 2    , or 1.0 x 2    , and
   *
   * -149 == -127 - 23 + 1.
   */
  #define	SNG_EXPBITS	8
  #define	SNG_FRACBITS	23
  
  #define	DBL_EXPBITS	11
  #define	DBL_FRACBITS	52
  
  #ifdef notyet
  #define	E80_EXPBITS	15
  #define	E80_FRACBITS	64
  #endif
  
  #define	EXT_EXPBITS	15
  #define	EXT_FRACBITS	112
  
  struct ieee_single {
  	u_int	sng_sign:1;
  	u_int	sng_exp:8;
  	u_int	sng_frac:23;
  };
  
  struct ieee_double {
  	u_int	dbl_sign:1;
  	u_int	dbl_exp:11;
  	u_int	dbl_frach:20;
  	u_int	dbl_fracl;
  };
  
  struct ieee_ext {
  	u_int	ext_sign:1;
  	u_int	ext_exp:15;
  	u_int	ext_frach:16;
  	u_int	ext_frachm;
  	u_int	ext_fraclm;
  	u_int	ext_fracl;
  };
  
  /*
   * Floats whose exponent is in [1..INFNAN) (of whatever type) are
   * `normal'.  Floats whose exponent is INFNAN are either Inf or NaN.
   * Floats whose exponent is zero are either zero (iff all fraction
   * bits are zero) or subnormal values.
   *
   * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its
   * high fraction; if the bit is set, it is a `quiet NaN'.
   */
  #define	SNG_EXP_INFNAN	255
  #define	DBL_EXP_INFNAN	2047
  #define	EXT_EXP_INFNAN	32767
  
  #if 0
  #define	SNG_QUIETNAN	(1 << 22)
  #define	DBL_QUIETNAN	(1 << 19)
  #define	EXT_QUIETNAN	(1 << 15)
  #endif
  
  /*
   * Exponent biases.
   */
  #define	SNG_EXP_BIAS	127
  #define	DBL_EXP_BIAS	1023
  #define	EXT_EXP_BIAS	16383
  