fp.h   [plain text]


/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
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/* Copyright (c) 1992, NeXT Computer, Inc.  All rights reserved.
 *
 *	File:	libc/m98k/gen/fp.h
 *	Author:	Derek B Clegg, NeXT Computer, Inc.
 *
 * HISTORY
 *  11-Nov-92  Derek B Clegg (dclegg@next.com)
 *	Created.
 *
 * Common definitions for floating-point numbers.
 */

/* The following definitions for for double precision IEEE format numbers. */

#define EXPONENT_BIAS 1023

#define SIGN_BITS 1
#define EXPONENT_BITS 11
#define FRACTION_BITS 52
#define HI_FRACTION_BITS 20
#define LO_FRACTION_BITS 32

struct double_format {
    unsigned sign: SIGN_BITS;
    unsigned exponent: EXPONENT_BITS;
    unsigned hi_fraction: HI_FRACTION_BITS;
    unsigned lo_fraction: LO_FRACTION_BITS;
};

union dbl {
    struct double_format s;
    unsigned int u[2];
    double value;
};

#define PlusInfinity	(1.0/0.0)
#define MinusInfinity	(-1.0/0.0)

#define not_a_number(x)		((x) != (x))
#define positive_infinity(x)	((x) == PlusInfinity)
#define negative_infinity(x)	((x) == MinusInfinity)