glibc/sysdeps/s390/fpu/s_roundeven.c

40 lines
1.3 KiB
C

/* roundeven() - S390 version.
Copyright (C) 2019-2020 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
<https://www.gnu.org/licenses/>. */
#ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
# include <math.h>
# include <libm-alias-double.h>
double
__roundeven (double x)
{
double y;
/* The z196 zarch "load fp integer" (fidbra) instruction is rounding
x to the nearest integer with "ties to even" rounding mode
(M3-field: 4) where inexact exceptions are suppressed (M4-field: 4). */
__asm__ ("fidbra %0,4,%1,4" : "=f" (y) : "f" (x));
return y;
}
hidden_def (__roundeven)
libm_alias_double (__roundeven, roundeven)
#else
# include <sysdeps/ieee754/dbl-64/s_roundeven.c>
#endif