minix/include/sys/ieee754.h
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

153 lines
4.7 KiB
C

/* $NetBSD: ieee754.h,v 1.7 2007/02/02 23:08:22 christos 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. 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
*/
#ifndef _SYS_IEEE754_H_
#define _SYS_IEEE754_H_
/*
* NOTICE: This is not a standalone file. To use it, #include it in
* your port's ieee.h header.
*/
#include <machine/endian.h>
/*
* <sys/ieee754.h> defines the layout of IEEE 754 floating point types.
* Only single-precision and double-precision types are defined here;
* extended types, if available, are defined in the machine-dependent
* header.
*/
/*
* 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
struct ieee_single {
#if _BYTE_ORDER == _BIG_ENDIAN
u_int sng_sign:1;
u_int sng_exp:SNG_EXPBITS;
u_int sng_frac:SNG_FRACBITS;
#else
u_int sng_frac:SNG_FRACBITS;
u_int sng_exp:SNG_EXPBITS;
u_int sng_sign:1;
#endif
};
#define DBL_EXPBITS 11
#define DBL_FRACHBITS 20
#define DBL_FRACLBITS 32
#define DBL_FRACBITS (DBL_FRACHBITS + DBL_FRACLBITS)
struct ieee_double {
#if _BYTE_ORDER == _BIG_ENDIAN
u_int dbl_sign:1;
u_int dbl_exp:DBL_EXPBITS;
u_int dbl_frach:DBL_FRACHBITS;
u_int dbl_fracl:DBL_FRACLBITS;
#else
u_int dbl_fracl:DBL_FRACLBITS;
u_int dbl_frach:DBL_FRACHBITS;
u_int dbl_exp:DBL_EXPBITS;
u_int dbl_sign:1;
#endif
};
/*
* 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.
*
* At least one `signalling NaN' and one `quiet NaN' value must be
* implemented. It is left to the architecture to specify how to
* distinguish between these.
*/
#define SNG_EXP_INFNAN 255
#define DBL_EXP_INFNAN 2047
/*
* Exponent biases.
*/
#define SNG_EXP_BIAS 127
#define DBL_EXP_BIAS 1023
/*
* Convenience data structures.
*/
union ieee_single_u {
float sngu_f;
struct ieee_single sngu_sng;
};
union ieee_double_u {
double dblu_d;
struct ieee_double dblu_dbl;
};
#endif /* _SYS_IEEE754_H_ */