ports/sysdeps/am33/fpu/fsetexcptflg.c

   1 /* Set floating-point environment exception handling.
   2    Copyright (C) 1998-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Alexandre Oliva <aoliva@redhat.com>
   5    based on corresponding file in the MIPS port.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library.  If not, see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 #include <fenv.h>
  22 #include <fpu_control.h>
  23 #include <shlib-compat.h>
  24
  25 int
  26 __fesetexceptflag (const fexcept_t *flagp, int excepts)
  27 {
  28   fpu_control_t cw, temp;
  29
  30   /* Get the current exceptions.  */
  31   _FPU_GETCW (cw);
  32
  33   /* Make sure the flags we want restored are legal.  */
  34   excepts &= FE_ALL_EXCEPT;
  35   temp = *flagp & excepts;
  36
  37   /* If EF bits are clear and the user requests them to be set,
  38      we have to fail, because there's no way to do it.  */
  39   if (~(cw & excepts) & temp)
  40     return -1;
  41
  42   /* We clear EF bits by storing a 1 in them, so flip the
  43      FE_ALL_EXCEPT bits.  */
  44   temp = (~temp & FE_ALL_EXCEPT);
  45
  46   /* Now clear the bits called for, and copy them in from flagp. Note that
  47      we ignore all non-flag bits from *flagp, so they don't matter.  */
  48   cw = (cw & ~FE_ALL_EXCEPT) | temp;
  49
  50   _FPU_SETFCW (cw);
  51
  52   /* Success.  */
  53   return 0;
  54 }
  55
  56 versioned_symbol (libm, __fesetexceptflag, fesetexceptflag, GLIBC_2_2);