/* * Copyright (C) 2007-2020 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/>. */ #ifndef _SOFT_FLOAT #if __PREC == 32 #define X87CW (0 << 8) /* Single precision (24 bits) */ #elif __PREC == 64 #define X87CW (2 << 8) /* Double precision (53 bits) */ #elif __PREC == 80 #define X87CW (3 << 8) /* Extended precision (64 bits) */ #else #error "Wrong precision requested." #endif #define X87CW_PCMASK (3 << 8) static void __attribute__((constructor)) set_precision (void) { unsigned short int cwd; asm volatile ("fnstcw\t%0" : "=m" (cwd)); cwd &= ~X87CW_PCMASK; cwd |= X87CW; asm volatile ("fldcw\t%0" : : "m" (cwd)); } #endif |