1/*	$OpenBSD: fpsetround.c,v 1.2 2021/04/30 16:13:00 drahn Exp $	*/
2/*
3 * Copyright (c) 2021 Mark Kettenis <kettenis@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#include <sys/types.h>
19#include <ieeefp.h>
20
21fp_rnd
22fpsetround(fp_rnd rnd_dir)
23{
24	uint32_t frm;
25
26	__asm volatile ("fsrm %0, %1" : "=r"(frm) : "r"(rnd_dir));
27
28	/* Truncating to 2 bits means both RNE and RMM become FP_RN. */
29	return frm & 0x3;
30}
31