gcc/libgcc/config/arm/crtfastmath.c

41 lines
1.4 KiB
C

/*
* Copyright (C) 2014 Free Software Foundation, Inc.
*
* This file is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 3, or (at your option) any
* later version.
*
* This file 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
* General Public License for more details.
*
* Under Section 7 of GPL version 3, you are granted additional
* permissions described in the GCC Runtime Library Exception, version
* 3.1, as published by the Free Software Foundation.
*
* You should have received a copy of the GNU General Public License and
* a copy of the GCC Runtime Library Exception along with this program;
* see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
* <http://www.gnu.org/licenses/>.
*/
/* Enable flush-to-zero support for -ffast-math on VFP targets. */
#ifndef __SOFTFP__
#define FPSCR_FZ (1 << 24)
static void __attribute__((constructor))
__arm_set_fast_math (void)
{
unsigned int fpscr_save;
/* Set the FZ (flush-to-zero) bit in FPSCR. */
__asm__("vmrs %0, fpscr" : "=r" (fpscr_save));
fpscr_save |= FPSCR_FZ;
__asm__("vmsr fpscr, %0" : : "r" (fpscr_save));
}
#endif /* __SOFTFP__ */