1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2012 Ian Lepore <freebsd@damnhippie.dyndns.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <fenv.h>
30 #include <float.h>
31
32 #ifndef __ARM_PCS_VFP
33 #include "softfloat-for-gcc.h"
34 #include "milieu.h"
35 #include "softfloat.h"
36 #endif
37
38 int
__flt_rounds(void)39 __flt_rounds(void)
40 {
41 int mode;
42
43 #ifndef __ARM_PCS_VFP
44 /*
45 * Translate our rounding modes to the unnamed
46 * manifest constants required by C99 et. al.
47 */
48 mode = __softfloat_float_rounding_mode;
49 #else /* __ARM_PCS_VFP */
50 /*
51 * Read the floating-point status and control register
52 */
53 __asm __volatile("vmrs %0, fpscr" : "=&r"(mode));
54 mode &= _ROUND_MASK;
55 #endif /* __ARM_PCS_VFP */
56
57 switch (mode) {
58 case FE_TOWARDZERO:
59 return (0);
60 case FE_TONEAREST:
61 return (1);
62 case FE_UPWARD:
63 return (2);
64 case FE_DOWNWARD:
65 return (3);
66 }
67 return (-1);
68 }
69