freebsd-dev/lib/libc/aarch64/gen/flt_rounds.c
Andrew Turner d422e6f9b5 Add the start of libc and libstand for arm64. Not all of the machine
dependent functions have been implemented, but this is enough for world.

Differential Revision:	https://reviews.freebsd.org/D2132
Reviewed by:	emaste
Sponsored by:	The FreeBSD Foundation
2015-04-07 09:52:14 +00:00

50 lines
1.7 KiB
C

/*-
* Copyright (c) 2012 Ian Lepore <freebsd@damnhippie.dyndns.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <fenv.h>
#include <float.h>
static int map[] = {
1, /* round to nearest */
2, /* round to positive infinity */
3, /* round to negative infinity */
0 /* round to zero */
};
int
__flt_rounds(void)
{
uint64_t fpcr;
asm volatile("mrs %0, fpcr" : "=r" (fpcr));
return map[(fpcr >> 22) & 3];
}