/* Raise given exceptions. Copyright (C) 1997, 1999, 2000, 2002 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by David Huggins-Daines The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include #include #include int feraiseexcept (int excepts) { /* Raise exceptions represented by EXCEPTS. But we must raise only one signal at a time. It is important that if the overflow/underflow exception and the divide by zero exception are given at the same time, the overflow/underflow exception follows the divide by zero exception. */ /* We do these bits in assembly to be certain GCC doesn't optimize away something important, and so we can force delayed traps to occur. */ /* FIXME: These all need verification! */ /* First: invalid exception. */ if (excepts & FE_INVALID) { /* One example of a invalid operation is 0 * Infinity. */ double d = HUGE_VAL; __asm__ __volatile__ ("fmpy,dbl %1,%%fr0,%0\n\t" /* FIXME: is this a proper trap barrier? */ "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d)); } /* Next: division by zero. */ if (excepts & FE_DIVBYZERO) { double d = 1.0; __asm__ __volatile__ ("fdiv,dbl %1,%%fr0,%0\n\t" "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d)); } /* Next: overflow. */ /* FIXME: Compare with IA-64 - do we have the same problem? */ if (excepts & FE_OVERFLOW) { double d = DBL_MAX; __asm__ __volatile__ ("fmpy,dbl %1,%1,%0\n\t" "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d)); } /* Next: underflow. */ if (excepts & FE_UNDERFLOW) { double d = DBL_MIN; double e = 69.69; __asm__ __volatile__ ("fdiv,dbl %1,%2,%0\n\t" "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d), "f" (e)); } /* Last: inexact. */ if (excepts & FE_INEXACT) { double d = 1.0; double e = M_PI; __asm__ __volatile__ ("fdiv,dbl %1,%2,%0\n\t" "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d), "f" (e)); } /* Success. */ return 0; } libm_hidden_def (feraiseexcept)