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/*
* Copyright (C) 1997-2022 Free Software Foundation, Inc.
*
* This file is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 3, or (at your option) any
* later version.
*
* This file 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
* General Public License for more details.
*
* Under Section 7 of GPL version 3, you are granted additional
* permissions described in the GCC Runtime Library Exception, version
* 3.1, as published by the Free Software Foundation.
*
* You should have received a copy of the GNU General Public License and
* a copy of the GCC Runtime Library Exception along with this program;
* see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include "sfp-machine.h"
#define HUGE_VAL (__builtin_huge_val ())
/* Please see section 10,
page 10-5 "Delayed Trapping" in the PA-RISC 2.0 Architecture manual */
void
__sfp_handle_exceptions (int _fex)
{
/* Raise exceptions represented by _FEX. 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. */
/* We use "fldd 0(%%sr0,%%sp),%0" to flush the delayed exception */
/* First: Invalid exception. */
if (_fex & FP_EX_INVALID)
{
/* One example of an invalid operation is 0 * Infinity. */
double d = HUGE_VAL;
__asm__ __volatile__ (
" fcpy,dbl %%fr0,%%fr22\n"
" fmpy,dbl %0,%%fr22,%0\n"
" fldd 0(%%sr0,%%sp),%0"
: "+f" (d) : : "%fr22" );
}
/* Second: Division by zero. */
if (_fex & FP_EX_DIVZERO)
{
double d = 1.0;
__asm__ __volatile__ (
" fcpy,dbl %%fr0,%%fr22\n"
" fdiv,dbl %0,%%fr22,%0\n"
" fldd 0(%%sr0,%%sp),%0"
: "+f" (d) : : "%fr22" );
}
/* Third: Overflow. */
if (_fex & FP_EX_OVERFLOW)
{
double d = __DBL_MAX__;
__asm__ __volatile__ (
" fadd,dbl %0,%0,%0\n"
" fldd 0(%%sr0,%%sp),%0"
: "+f" (d) );
}
/* Fourth: Underflow. */
if (_fex & FP_EX_UNDERFLOW)
{
double d = __DBL_MIN__;
double e = 3.0;
__asm__ __volatile__ (
" fdiv,dbl %0,%1,%0\n"
" fldd 0(%%sr0,%%sp),%0"
: "+f" (d) : "f" (e) );
}
/* Fifth: Inexact */
if (_fex & FP_EX_INEXACT)
{
double d = 3.14159265358979323846;
double e = 69.69;
__asm__ __volatile__ (
" fdiv,dbl %0,%1,%%fr22\n"
" fcnvfxt,dbl,sgl %%fr22,%%fr22L\n"
" fldd 0(%%sr0,%%sp),%%fr22"
: : "f" (d), "f" (e) : "%fr22" );
}
}
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