1/* $NetBSD: systmodes.S,v 1.3 2001/03/22 12:05:36 ross Exp $ */
2
3/* This is a derivative work. */
4
5/*-
6 * Copyright (c) 2001 The NetBSD Foundation, Inc.
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to The NetBSD Foundation
10 * by Ross Harvey.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 *    must display the following acknowledgement:
22 *        This product includes software developed by the NetBSD
23 *        Foundation, Inc. and its contributors.
24 * 4. Neither the name of The NetBSD Foundation nor the names of its
25 *    contributors may be used to endorse or promote products derived
26 *    from this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
30 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
31 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
32 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 */
40
41/*
42===============================================================================
43
44This GNU assembler source file is part of TestFloat, Release 2a, a package
45of programs for testing the correctness of floating-point arithmetic
46complying to the IEC/IEEE Standard for Floating-Point.
47
48Written by John R. Hauser.  More information is available through the Web
49page `http://HTTP.CS.Berkeley.EDU/~jhauser/arithmetic/TestFloat.html'.
50
51THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort
52has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
53TIMES RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO
54PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
55AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
56
57Derivative works are acceptable, even for commercial purposes, so long as
58(1) they include prominent notice that the work is derivative, and (2) they
59include prominent notice akin to these four paragraphs for those parts of
60this code that are retained.
61
62===============================================================================
63*/
64
65	.text
66
67#include <machine/asm.h>
68
69/*
70-------------------------------------------------------------------------------
71Sets the rounding precision of subsequent extended double-precision
72operations.  The `precision' argument should be one of 0, 32, 64, or 80.
73If `precision' is 32, the rounding precision is set equivalent to single
74precision; else if `precision' is 64, the rounding precision is set
75equivalent to double precision; else the rounding precision is set to full
76extended double precision.
77-------------------------------------------------------------------------------
78*/
79
80ENTRY(syst_float_set_rounding_precision)
81	movb 4(%esp),%al
82	movb $0,%ah
83	cmpb $32,%al
84	je setRoundingPrecision
85	movb $2,%ah
86	cmpb $64,%al
87	je setRoundingPrecision
88	movb $3,%ah
89	cmpb $80,%al
90	je setRoundingPrecision
91	movb $0,%ah
92setRoundingPrecision:
93	movb $0,%al
94	subl $2,%esp
95	fnstcw 0(%esp)
96	andw $64767,0(%esp)
97	orw %ax,0(%esp)
98	fldcw 0(%esp)
99	addl $2,%esp
100	ret
101
102