1 /*
2 * Copyright (C) 2014-2016 Free Software Foundation, Inc.
3 *
4 * This file is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation; either version 3, or (at your option) any
7 * later version.
8 *
9 * This file is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * Under Section 7 of GPL version 3, you are granted additional
15 * permissions described in the GCC Runtime Library Exception, version
16 * 3.1, as published by the Free Software Foundation.
17 *
18 * You should have received a copy of the GNU General Public License and
19 * a copy of the GCC Runtime Library Exception along with this program;
20 * see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
21 * <http://www.gnu.org/licenses/>.
22 */
23
24 /* Enable flush-to-zero support for -ffast-math on VFP targets. */
25 #ifndef __SOFTFP__
26
27 #define FPSCR_FZ (1 << 24)
28
29 static void __attribute__((constructor))
__arm_set_fast_math(void)30 __arm_set_fast_math (void)
31 {
32 unsigned int fpscr_save;
33
34 /* Set the FZ (flush-to-zero) bit in FPSCR. */
35 __asm__("vmrs %0, fpscr" : "=r" (fpscr_save));
36 fpscr_save |= FPSCR_FZ;
37 __asm__("vmsr fpscr, %0" : : "r" (fpscr_save));
38 }
39
40 #endif /* __SOFTFP__ */
41