xref: /freebsd/lib/msun/i387/s_tan.S (revision 952d112864d8008aa87278a30a539d888a8493cd)
1/*
2 * Copyright (c) 1994 Winning Strategies, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *      This product includes software developed by Winning Strategies, Inc.
16 * 4. The name of the author may not be used to endorse or promote products
17 *    derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31/*
32 * Written by:
33 *	J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
34 */
35
36#include <machine/asm.h>
37
38RCSID("$Id: s_tan.S,v 1.4 1997/02/22 15:09:06 peter Exp $")
39
40ENTRY(tan)
41	fldl	4(%esp)
42	fptan
43	fnstsw	%ax
44	andw	$0x400,%ax
45	jnz	1f
46	fstp	%st(0)
47	ret
481:	fldpi
49	fadd	%st(0)
50	fxch	%st(1)
512:	fprem1
52	fstsw	%ax
53	andw	$0x400,%ax
54	jnz	2b
55	fstp	%st(1)
56	fptan
57	fstp	%st(0)
58	ret
59