NetBSD/lib/libc/gen/ieee754_isinf.c
simonb 2d8577fb83 Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
 - Use the above for the __infinity and __nan constants on all
   architectures that use the standard ieee754 representation of
   those constants.
 - Add a single copy of various ieee754 math functions (frexp, isinf,
   isnan, ldexp and modf) that had numerous duplicates among the
   arch-specific directories.
 - Use the above functions on all architectures where the generic C
   versions where used.  Architectures that had local assembly
   routines are untouched (for those functions only).
2002-02-19 13:08:12 +00:00

72 lines
2.7 KiB
C

/* $NetBSD: ieee754_isinf.c,v 1.1 2002/02/19 13:08:13 simonb 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.
*
* 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.
*
* from: Header: isinf.c,v 1.1 91/07/08 19:03:34 torek Exp
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)isinf.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: ieee754_isinf.c,v 1.1 2002/02/19 13:08:13 simonb Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <sys/types.h>
#include <machine/ieee.h>
#include <math.h>
#ifdef __weak_alias
__weak_alias(isinf,_isinf)
#endif
int
isinf(double d)
{
union {
double d;
struct ieee_double dbl;
} u;
u.d = d;
return (u.dbl.dbl_exp == DBL_EXP_INFNAN &&
(u.dbl.dbl_frach == 0 && u.dbl.dbl_fracl == 0));
}