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50 lines
1.5 KiB
C
50 lines
1.5 KiB
C
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/* Enable floating-point exceptions.
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Copyright (C) 2001 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Andreas Jaeger <aj@suse.de>, 2001.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <fenv.h>
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int
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feenableexcept (int excepts)
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{
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unsigned short int new_exc, old_exc;
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unsigned int new, old;
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excepts &= FE_ALL_EXCEPT;
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/* Get the current control word of the x87 FPU. */
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__asm__ ("fstcw %0" : "=m" (*&new_exc));
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old_exc = (~new_exc) & FE_ALL_EXCEPT;
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new_exc &= ~excepts;
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__asm__ ("fldcw %0" : : "m" (*&new_exc));
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/* And now the same for the SSE MXCSR register. */
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__asm__ ("stmxcsr %0" : "=m" (*&new));
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/* The SSE exception masks are shifted by 7 bits. */
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old = (~new) & (FE_ALL_EXCEPT << 7);
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new &= ~(excepts << 7);
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__asm__ ("ldmxcsr %0" : : "m" (*&new));
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return old_exc;
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}
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