glibc/sysdeps/alpha/fpu/fraiseexcpt.c

71 lines
2.5 KiB
C

/* Raise given exceptions.
Copyright (C) 1997, 1998, 1999, 2000 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>
int
__feraiseexcept (int excepts)
{
double tmp;
double 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));
/* Success. */
return 0;
}
strong_alias (__feraiseexcept, __old_feraiseexcept)
symbol_version (__old_feraiseexcept, feraiseexcept, GLIBC_2.1);
default_symbol_version (__feraiseexcept, feraiseexcept, GLIBC_2.2);