flt_rounds.c revision 230191 
1144513Simp/*-
2144513Simp * Copyright (c) 2012 Ian Lepore <freebsd@damnhippie.dyndns.org>
3144513Simp * All rights reserved.
4144513Simp *
5144513Simp * Redistribution and use in source and binary forms, with or without
6217157Stijl * 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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/lib/libc/arm/gen/flt_rounds.c 230191 2012-01-16 04:08:29Z das $");
29
30#include <fenv.h>
31#include <float.h>
32
33#include "softfloat.h"
34
35int
36__flt_rounds(void)
37{
38
39#ifndef ARM_HARD_FLOAT
40	/*
41	 * Translate our rounding modes to the unnamed
42	 * manifest constants required by C99 et. al.
43	 */
44	switch (__softfloat_float_rounding_mode) {
45	case FE_TOWARDZERO:
46		return (0);
47	case FE_TONEAREST:
48		return (1);
49	case FE_UPWARD:
50		return (2);
51	case FE_DOWNWARD:
52		return (3);
53	}
54	return (-1);
55#else /* ARM_HARD_FLOAT */
56	/*
57	 * Apparently, the rounding mode is specified as part of the
58	 * instruction format on ARM, so the dynamic rounding mode is
59	 * indeterminate.  Some FPUs may differ.
60	 */
61	return (-1);
62#endif /* ARM_HARD_FLOAT */
63}
64