?? fsetexcptflg.c
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/* Set floating-point environment exception handling. Copyright (C) 2001, 2003 Free Software Foundation, Inc. This file is part of the GNU C Library. 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, 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 <math.h>intfesetexceptflag (const fexcept_t *flagp, int excepts){ fenv_t temp; unsigned int mxcsr; /* XXX: Do we really need to set both the exception in both units? Shouldn't it be enough to set only the SSE unit? */ /* Get the current x87 FPU environment. We have to do this since we cannot separately set the status word. */ __asm__ ("fnstenv %0" : "=m" (*&temp)); temp.__status_word &= ~(excepts & FE_ALL_EXCEPT); temp.__status_word |= *flagp & excepts & FE_ALL_EXCEPT; /* Store the new status word (along with the rest of the environment. Possibly new exceptions are set but they won't get executed unless the next floating-point instruction. */ __asm__ ("fldenv %0" : : "m" (*&temp)); /* And now the same for SSE. */ __asm__ ("stmxcsr %0" : "=m" (*&mxcsr)); mxcsr &= ~(excepts & FE_ALL_EXCEPT); mxcsr |= *flagp & excepts & FE_ALL_EXCEPT; __asm__ ("ldmxcsr %0" : : "m" (*&mxcsr)); /* Success. */ return 0;}
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