/* Set current rounding direction. Copyright (C) 1997, 2003, 2004, 2005 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. 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, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include <fenv.h> #include <unistd.h> int fesetround (int round) { unsigned short int cw; if ((round & ~0xc00) != 0) /* ROUND is no valid rounding mode. */ return 1; __asm__ ("fnstcw %0" : "=m" (*&cw)); cw &= ~0xc00; cw |= round; __asm__ ("fldcw %0" : : "m" (*&cw)); #if 0 /* If the CPU supports SSE we set the MXCSR as well. */ if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0) { unsigned int xcw; __asm__ ("stmxcsr %0" : "=m" (*&xcw)); xcw &= ~0x6000; xcw |= round << 3; __asm__ ("ldmxcsr %0" : : "m" (*&xcw)); } #endif return 0; }