glibc/sysdeps/arm/setfpucw.c

44 lines
1.3 KiB
C

/* Set the FPU control word.
Copyright (C) 1996-2015 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 <fpu_control.h>
#include <arm-features.h>
void
__setfpucw (fpu_control_t set)
{
fpu_control_t fpscr, new_fpscr;
/* Do nothing if a VFP unit isn't present. */
if (!ARM_HAVE_VFP)
return;
_FPU_GETCW (fpscr);
/* Preserve the reserved bits, and set the rest as the user
specified (or the default, if the user gave zero). */
new_fpscr = fpscr & _FPU_RESERVED;
new_fpscr |= set & ~_FPU_RESERVED;
/* Write FPSCR if changed. */
if (new_fpscr != fpscr)
_FPU_SETCW (fpscr);
}