glibc/sysdeps/unix/sysv/linux/alpha/fraiseexcpt.c

93 lines
3.2 KiB
C

/* Copyright (C) 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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 <fenv_libc.h>
#include <sysdep.h>
#include <float.h>
#include "kernel-features.h"
#include "kernel_sysinfo.h"
int
__feraiseexcept (int excepts)
{
INTERNAL_SYSCALL_DECL (err);
unsigned long t = excepts;
long r;
r = INTERNAL_SYSCALL (osf_setsysinfo, err, 2, SSI_IEEE_RAISE_EXCEPTION, &t);
#ifndef __ASSUME_IEEE_RAISE_EXCEPTION
if (!INTERNAL_SYSCALL_ERROR_P (r, err))
return 0;
double d;
/* If we got an error from SSI_IEEE_RAISE_EXCEPTION, assume it means that
the system call isn't actually implemented. Do the best we can. */
/* Invalid implemented with 0 / 0 -> NaN. */
if (excepts & FE_INVALID)
__asm__ __volatile__ ("divs/su $f31,$f31,%0; trapb" : "=f"(d) : );
/* Division By Zero implemented with 1 / 0 -> NaN. */
if (excepts & FE_DIVBYZERO)
__asm__ __volatile__ ("divs/su %1,$f31,%0; trapb" : "=&f"(d) : "f"(1.0f));
/* Overflow and underflow cannot be had all by themselves. We can
generate them with arithmetic, but we always get INEXACT raised
at the same time. Prepare to undo. */
if ((excepts & (FE_OVERFLOW | FE_UNDERFLOW)) && !(excepts & FE_INEXACT))
INTERNAL_SYSCALL (osf_getsysinfo, err, 2, GSI_IEEE_FP_CONTROL, &t);
/* Overflow implemented with FLT_MAX + FLT_MAX -> Inf. */
if (excepts & FE_OVERFLOW)
__asm__ __volatile__ ("adds/sui %1,%1,%0; trapb"
: "=&f"(d) : "f"(FLT_MAX));
/* Underflow implemented with FLT_MIN * FLT_MIN -> 0. */
if (excepts & FE_UNDERFLOW)
__asm__ __volatile__ ("muls/sui %1,%1,%0; trapb"
: "=&f"(d) : "f"(FLT_MIN));
/* Inexact implemented with (long)0.5 -> 0. */
if ((excepts & (FE_OVERFLOW | FE_UNDERFLOW | FE_INEXACT)) == FE_INEXACT)
__asm__ __volatile__ ("cvttq/svi %1,%0; trapb" : "=&f"(d) : "f"(0.5f));
/* If we raised inexact when not asked, and inexact was not previously
raised, then clear that exception. */
if ((excepts & (FE_OVERFLOW | FE_UNDERFLOW))
&& !((excepts | t) & FE_INEXACT))
{
t |= excepts & SWCR_STATUS_MASK;
INTERNAL_SYSCALL (osf_setsysinfo, err, 2, SSI_IEEE_FP_CONTROL, &t);
}
#endif /* !__ASSUME_IEEE_RAISE_EXCEPTION */
return 0;
}
#include <shlib-compat.h>
#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
strong_alias (__feraiseexcept, __old_feraiseexcept)
compat_symbol (libm, __old_feraiseexcept, feraiseexcept, GLIBC_2_1);
#endif
libm_hidden_ver (__feraiseexcept, feraiseexcept)
versioned_symbol (libm, __feraiseexcept, feraiseexcept, GLIBC_2_2);