xref: /illumos-gate/usr/src/lib/libm/amd64/src/acosl.S (revision 55fea89d)
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 2005 Sun Microsystems, Inc.  All rights reserved.
26 * Use is subject to license terms.
27 */
28
29        .file "acosl.s"
30
31#include "libm.h"
32LIBM_ANSI_PRAGMA_WEAK(acosl,function)
33
34	ENTRY(acosl)
35	fldt	8(%rsp)			/ push x
36	fld1				/ push 1
37	fld	%st(1)			/ x , 1 , x
38	fabs				/ |x| , 1 , x
39	fucomip	%st(1),%st
40	ja	9f
41	fadd	%st(1),%st		/ 1+x,x
42	fldz
43	fucomip	%st(1),%st
44	jp	.L1
45	jne	.L1
46	/ x is -1
47	fstp	%st(0)			/ -1
48	fstp	%st(0)			/ empty NPX stack
49	fldpi
50	ret
51.L1:
52	fxch	%st(1)			/ x,1+x
53	fld1				/ 1,x,1+x
54	fsubp	%st,%st(1)		/ 1-x,1+x
55	fdivp	%st,%st(1)		/ (1-x)/(1+x)
56	fsqrt
57	fld1				/ 1,sqrt((1-x)/(1+x))
58	fpatan
59	fadd	%st(0),%st
60	ret
619:
62	/ |x| > 1
63	fstp	%st(0)			/ x
64	fsub	%st,%st(0)		/ +/-0 or NaN+invalid
65	fdiv	%st,%st(0)		/ NaN+invalid or NaN
66	ret
67	.align	16
68	SET_SIZE(acosl)
69