xref: /titanic_51/usr/src/lib/libm/i386/src/finitel.s (revision ddc0e0b53c661f6e439e3b7072b3ef353eadb4af)
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 "finitel.s"
30
31#include "libm.h"
32
33	ENTRY(finitel)
34	movl    12(%esp),%eax		/ %ax <-- sign&bexp(x)
35	testl	$0x80000000,8(%esp)	/ ZF = 1 iff hi_32(sgnfcnd(x))'s msb = 0
36	jz	.chk_denormal_or_0
37	notl	%eax			/ not(bexp) = 0 iff bexp = all 1's
38	andl    $0x00007fff,%eax	/ ZF <-- 1      iff not(bexp) = 0
39	jz	.done			/ no jump if arg. is finite
40	movl	$1,%eax			/ ansi needs %eax = 1
41.done:
42	ret
43
44.chk_denormal_or_0:
45	andl	$0x00007fff,%eax	/ ZF <-- 1 iff bexp = 0 iff denormal or 0
46	jnz	.unsupported		/ jump if arg has unsupported format
47	movl	$1,%eax			/ ansi needs %eax = 1
48	ret
49
50.unsupported:
51	movl	$0,%eax			/ unsupported format does not represent
52	ret				/ a finite number
53	.align	4
54	SET_SIZE(finitel)
55