xref: /minix3/lib/libc/arch/riscv/gen/flt_rounds.c (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1*0a6a1f1dSLionel Sambuc /*	$NetBSD: flt_rounds.c,v 1.2 2015/03/19 21:22:59 joerg Exp $	*/
2*0a6a1f1dSLionel Sambuc 
3*0a6a1f1dSLionel Sambuc /*-
4*0a6a1f1dSLionel Sambuc  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5*0a6a1f1dSLionel Sambuc  * All rights reserved.
6*0a6a1f1dSLionel Sambuc  *
7*0a6a1f1dSLionel Sambuc  * This code is derived from software contributed to The NetBSD Foundation
8*0a6a1f1dSLionel Sambuc  * by Matt Thomas of 3am Software Foundry.
9*0a6a1f1dSLionel Sambuc  *
10*0a6a1f1dSLionel Sambuc  * Redistribution and use in source and binary forms, with or without
11*0a6a1f1dSLionel Sambuc  * modification, are permitted provided that the following conditions
12*0a6a1f1dSLionel Sambuc  * are met:
13*0a6a1f1dSLionel Sambuc  * 1. Redistributions of source code must retain the above copyright
14*0a6a1f1dSLionel Sambuc  *    notice, this list of conditions and the following disclaimer.
15*0a6a1f1dSLionel Sambuc  * 2. Redistributions in binary form must reproduce the above copyright
16*0a6a1f1dSLionel Sambuc  *    notice, this list of conditions and the following disclaimer in the
17*0a6a1f1dSLionel Sambuc  *    documentation and/or other materials provided with the distribution.
18*0a6a1f1dSLionel Sambuc  *
19*0a6a1f1dSLionel Sambuc  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20*0a6a1f1dSLionel Sambuc  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21*0a6a1f1dSLionel Sambuc  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22*0a6a1f1dSLionel Sambuc  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23*0a6a1f1dSLionel Sambuc  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24*0a6a1f1dSLionel Sambuc  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25*0a6a1f1dSLionel Sambuc  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26*0a6a1f1dSLionel Sambuc  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27*0a6a1f1dSLionel Sambuc  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28*0a6a1f1dSLionel Sambuc  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29*0a6a1f1dSLionel Sambuc  * POSSIBILITY OF SUCH DAMAGE.
30*0a6a1f1dSLionel Sambuc  */
31*0a6a1f1dSLionel Sambuc 
32*0a6a1f1dSLionel Sambuc #include <sys/cdefs.h>
33*0a6a1f1dSLionel Sambuc #if defined(LIBC_SCCS) && !defined(lint)
34*0a6a1f1dSLionel Sambuc __RCSID("$NetBSD: flt_rounds.c,v 1.2 2015/03/19 21:22:59 joerg Exp $");
35*0a6a1f1dSLionel Sambuc #endif /* LIBC_SCCS and not lint */
36*0a6a1f1dSLionel Sambuc 
37*0a6a1f1dSLionel Sambuc #include "namespace.h"
38*0a6a1f1dSLionel Sambuc #include <ieeefp.h>
39*0a6a1f1dSLionel Sambuc #include <float.h>
40*0a6a1f1dSLionel Sambuc #include <stdint.h>
41*0a6a1f1dSLionel Sambuc #include <machine/ieeefp.h>
42*0a6a1f1dSLionel Sambuc 
43*0a6a1f1dSLionel Sambuc static const int rounding_map =
44*0a6a1f1dSLionel Sambuc 	  (1 << (FP_RN * 2))	/* round to nearest */
45*0a6a1f1dSLionel Sambuc 	| (0 << (FP_RZ * 2))	/* round to zero */
46*0a6a1f1dSLionel Sambuc 	| (2 << (FP_RP * 2))	/* round to positive infinity */
47*0a6a1f1dSLionel Sambuc 	| (3 << (FP_RM * 2));	/* round to negative infinity */
48*0a6a1f1dSLionel Sambuc 
49*0a6a1f1dSLionel Sambuc int
__flt_rounds(void)50*0a6a1f1dSLionel Sambuc __flt_rounds(void)
51*0a6a1f1dSLionel Sambuc {
52*0a6a1f1dSLionel Sambuc 	return (rounding_map >> (fpgetround() * 2)) & 3;
53*0a6a1f1dSLionel Sambuc }
54