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/* Raise given exceptions.
Copyright (C) 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. 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>
void
feraiseexcept (int excepts)
{
double tmp, dummy;
/* Raise exceptions represented by EXPECTS. But we must raise only
one signal at a time. It is important the if the overflow/underflow
exception and the inexact exception are given at the same time,
the overflow/underflow exception precedes the inexact exception. */
/* We do these bits in assembly to be certain GCC doesn't optimize
away something important. */
/* First: invalid exception. */
if (FE_INVALID & excepts)
{
/* One example of a invalid operation is 0 * Infinity. */
__asm__ __volatile__("mult/sui $f31,%1,%0; trapb"
: "=&f"(tmp) : "f"(HUGE_VAL));
}
/* Next: division by zero. */
if (FE_DIVBYZERO & excepts)
{
__asm__ __volatile__("cmpteq $f31,$f31,%1; divt/sui %1,$f31,%0; trapb"
: "=&f"(tmp), "=f"(dummy));
}
/* Next: overflow. */
if (FE_OVERFLOW & excepts)
{
__asm__ __volatile__("mult/sui %1,%1,%0; trapb"
: "=&f"(tmp) : "f"(DBL_MAX));
}
/* Next: underflow. */
if (FE_UNDERFLOW & excepts)
{
__asm__ __volatile__("divt/sui %1,%2,%0; trapb"
: "=&f"(tmp) : "f"(DBL_MIN),
"f"((double) (1UL << 60)));
}
/* Last: inexact. */
if (FE_INEXACT & excepts)
{
__asm__ __volatile__("divt/sui %1,%2,%0; trapb"
: "=&f"(tmp) : "f"(1.0), "f"(M_PI));
}
}
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