xref: /illumos-gate/usr/src/lib/libm/i386/src/asinl.S (revision 5d9d9091f564c198a760790b0bfa72c44e17912b)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
23 */
24/*
25 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
26 * Use is subject to license terms.
27 */
28
29	.file	"asinl.s"
30
31#include "libm.h"
32LIBM_ANSI_PRAGMA_WEAK(asinl,function)
33
34	ENTRY(asinl)
35	fldt	4(%esp)			/ push x
36	fld1				/ push 1
37	fld	%st(1)			/ x , 1 , x
38	fabs				/ |x| , 1 , x
39	fucomp
40	fstsw	%ax
41	sahf
42	ja	9f
43	fadd	%st(1),%st		/ 1+x,x
44	fld1				/ 1,1+x,x
45	fsub	%st(2),%st		/ 1-x,1+x,x
46	fmulp	%st,%st(1)		/ (1-x)*(1+x),x
47	fsqrt				/ sqrt((1-x)*(1+x)),x
48	fpatan				/ atan(x/sqrt((1-x)*(1+x)))
49	ret
509:
51	/ |x| > 1
52	fstp	%st(0)			/ x
53	fsub	%st,%st(0)		/ +/-0 or NaN+invalid
54	fdiv	%st,%st(0)		/ NaN+invalid or NaN
55	ret
56	.align	4
57	SET_SIZE(asinl)
58