isnan.s revision 25c28e83beb90e7c80452a7c818c5e6f73a07dc8
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.file "isnan.s"
#include "libm.h"
LIBM_ANSI_PRAGMA_WEAK(isnan,function)
.weak _isnan
.type _isnan,@function
_isnan = __isnan
.weak _isnand
.type _isnand,@function
_isnand = __isnan
.weak isnand
.type isnand,@function
isnand = __isnan
#include "libm_synonyms.h"
ENTRY(isnan)
movl 8(%esp),%eax / eax <-- hi_32(x)
andl $0x7fffffff,%eax / eax <-- hi_32(abs(x))
subl $0x7ff00000,%eax / weed out finite values
jae .nan_or_inf / no jump if arg. is finite
movl $0,%eax / ansi needs (eax) = 0
ret
.nan_or_inf:
ja .got_nan / no jump if arg. may be infinite;
/ let nan waste time
/ (eax) = 0 here
testl $0xffffffff,4(%esp) / ZF <-- 1 iff lo_frac. = 0
/ iff arg. is infinite
jnz .got_nan / no jump if arg. is infinite;
ret
.got_nan:
movl $1,%eax / %eax was 0, must be made 1 to
/ indicate TRUE
ret
.align 4
SET_SIZE(isnan)