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/* Round long double to integer away from zero.
Copyright (C) 1997-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
Jakub Jelinek <jj@ultra.linux.cz>, 1999.
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, see
<http://www.gnu.org/licenses/>. */
#include <math.h>
#include <math_private.h>
static const long double huge = 1.0E4930L;
long double
__roundl (long double x)
{
int32_t j0;
u_int64_t i1, i0;
GET_LDOUBLE_WORDS64 (i0, i1, x);
j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
if (j0 < 48)
{
if (j0 < 0)
{
if (huge + x > 0.0)
{
i0 &= 0x8000000000000000ULL;
if (j0 == -1)
i0 |= 0x3fff000000000000LL;
i1 = 0;
}
}
else
{
u_int64_t i = 0x0000ffffffffffffLL >> j0;
if (((i0 & i) | i1) == 0)
/* X is integral. */
return x;
if (huge + x > 0.0)
{
/* Raise inexact if x != 0. */
i0 += 0x0000800000000000LL >> j0;
i0 &= ~i;
i1 = 0;
}
}
}
else if (j0 > 111)
{
if (j0 == 0x4000)
/* Inf or NaN. */
return x + x;
else
return x;
}
else
{
u_int64_t i = -1ULL >> (j0 - 48);
if ((i1 & i) == 0)
/* X is integral. */
return x;
if (huge + x > 0.0)
{
/* Raise inexact if x != 0. */
u_int64_t j = i1 + (1LL << (111 - j0));
if (j < i1)
i0 += 1;
i1 = j;
}
i1 &= ~i;
}
SET_LDOUBLE_WORDS64 (x, i0, i1);
return x;
}
weak_alias (__roundl, roundl)
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