libm/x86_64/ftestexcept.c

   1 /* Test exception in current environment.
   2    Copyright (C) 2001-2017 Free Software Foundation, Inc.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <fenv.h>
  19
  20 int
  21 fetestexcept (int excepts)
  22 {
  23   int temp;
  24   unsigned int mxscr;
  25
  26   /* Get current exceptions.  */
  27   __asm__ ("fnstsw %0\n"
  28            "stmxcsr %1" : "=m" (*&temp), "=m" (*&mxscr));
  29
  30   return (temp | mxscr) & excepts & FE_ALL_EXCEPT;
  31 }