glibc/sysdeps/riscv/rv64/rvd/s_nearbyint.c
Joseph Myers 04277e02d7 Update copyright dates with scripts/update-copyrights.
* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.
2019-01-01 00:11:28 +00:00

53 lines
1.5 KiB
C

/* nearbyint(). RISC-V version.
Copyright (C) 2017-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
#include <math.h>
#include <fenv_private.h>
#include <libm-alias-double.h>
#include <stdint.h>
double
__nearbyint (double x)
{
int flags = riscv_getflags ();
bool nan = isnan (x);
double mag = fabs (x);
if (nan)
return x + x;
if (mag < (1ULL << __DBL_MANT_DIG__))
{
int64_t i;
double new_x;
asm volatile ("fcvt.l.d %0, %1" : "=r" (i) : "f" (x));
asm volatile ("fcvt.d.l %0, %1" : "=f" (new_x) : "r" (i));
/* nearbyint(-0) == -0, and in general we'll always have the same
sign as our input. */
x = copysign (new_x, x);
riscv_setflags (flags);
}
return x;
}
libm_alias_double (__nearbyint, nearbyint)