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/* Round long double to integer away from zero.
Copyright (C) 1997, 2007, 2011 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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_int32_t se, i1, i0;
GET_LDOUBLE_WORDS (se, i0, i1, x);
j0 = (se & 0x7fff) - 0x3fff;
if (j0 < 31)
{
if (j0 < 0)
{
math_force_eval (huge + x);
se &= 0x8000;
i0 = i1 = 0;
if (j0 == -1)
{
se |= 0x3fff;
i0 = 0x80000000;
}
}
else
{
u_int32_t i = 0x7fffffff >> j0;
if (((i0 & i) | i1) == 0)
/* X is integral. */
return x;
/* Raise inexact if x != 0. */
math_force_eval (huge + x);
u_int32_t j = i0 + (0x40000000 >> j0);
if (j < i0)
se += 1;
i0 = (j & ~i) | 0x80000000;
i1 = 0;
}
}
else if (j0 > 62)
{
if (j0 == 0x4000)
/* Inf or NaN. */
return x + x;
else
return x;
}
else
{
u_int32_t i = 0xffffffff >> (j0 - 31);
if ((i1 & i) == 0)
/* X is integral. */
return x;
math_force_eval (huge + x);
/* Raise inexact if x != 0. */
u_int32_t j = i1 + (1 << (62 - j0));
if (j < i1)
{
u_int32_t k = i0 + 1;
if (k < i0)
{
se += 1;
k |= 0x80000000;
}
i0 = k;
}
i1 = j;
i1 &= ~i;
}
SET_LDOUBLE_WORDS (x, se, i0, i1);
return x;
}
weak_alias (__roundl, roundl)
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