gcc-4_9-branch/libgcc/config/aarch64/crtfastmath.c

   1 /*
   2  * Copyright (C) 2014 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 #define _FPU_FPCR_FZ 0x1000000
  25
  26 #define _FPU_SETCW(fpcr)                                   \
  27   {                                                        \
  28     __asm__ __volatile__ ("msr  fpcr, %0" : : "r" (fpcr)); \
  29   }
  30
  31 static void __attribute__((constructor))
  32 set_fast_math (void)
  33 {
  34   /* Flush to zero, round to nearest, IEEE exceptions disabled.  */
  35   _FPU_SETCW (_FPU_FPCR_FZ);
  36 }