/* Software floating-point emulation.
Convert IEEE extended to signed or unsigned _BitInt.
Copyright (C) 2023 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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.
GCC 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 "soft-fp.h"
#include "extended.h"
#include "bitint.h"
#ifdef __BITINT_MAXWIDTH__
#ifndef TI_BITS
/* While mantissa is 64 bits including 1 explicit bit, extended.h uses
op-2.h for W_TYPE_SIZE 64 and op-4.h for W_TYPE_SIZE 32, so we have
to use 128-bit type here. On most 32-bit architectures TImode isn't
supported, so use _BitInt(128) instead. */
typedef _BitInt(128) TItype;
typedef unsigned _BitInt(128) UTItype;
#define TI_BITS 128
#endif
void
__fixxfbitint (UBILtype *r, SItype rprec, XFtype a)
{
FP_DECL_EX;
FP_DECL_E (A);
USItype arprec = rprec < 0 ? -rprec : rprec;
USItype rn = ((USItype) arprec + BIL_TYPE_SIZE - 1) / BIL_TYPE_SIZE;
UTItype rv;
USItype rsize = arprec > TI_BITS ? TI_BITS : arprec;
USItype rsigned = rprec < 0;
USItype ovf = 0;
USItype shift = 0;
FP_INIT_EXCEPTIONS;
FP_UNPACK_RAW_E (A, a);
if (arprec > TI_BITS)
{
if (A_e < _FP_EXPBIAS_E || (A_s && !rsigned))
ovf = 1;
else if (A_e >= (_FP_EXPMAX_E < _FP_EXPBIAS_E + arprec
? _FP_EXPMAX_E
: _FP_EXPBIAS_E + arprec - rsigned))
{
ovf = 1;
if (A_s
&& A_e == _FP_EXPBIAS_E + arprec - 1
&& A_e < _FP_EXPMAX_E)
A_e -= arprec - TI_BITS;
}
else if (A_e >= _FP_EXPBIAS_E + TI_BITS - rsigned)
{
shift = A_e - (_FP_EXPBIAS_E + TI_BITS - rsigned - 1);
A_e -= shift;
}
}
FP_TO_INT_E (rv, A, rsize, rsigned);
FP_HANDLE_EXCEPTIONS;
FP_TO_BITINT (r, rn, arprec, shift, rv, rsize, rsigned, ovf, TI);
}
#endif
