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/* Round argument to nearest integral value according to current rounding
direction.
Copyright (C) 1997-2021 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
<https://www.gnu.org/licenses/>. */
#include <fenv.h>
#include <limits.h>
#include <math.h>
#include <math_private.h>
#include <libm-alias-ldouble.h>
static const long double two63[2] =
{
9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */
-9.223372036854775808000000e+18 /* 0xC03E, 0x00000000, 0x00000000 */
};
long int
__lrintl (long double x)
{
int32_t se,j0;
uint32_t i0, i1;
long int result;
long double w;
long double t;
int sx;
GET_LDOUBLE_WORDS (se, i0, i1, x);
sx = (se >> 15) & 1;
j0 = (se & 0x7fff) - 0x3fff;
if (j0 < 31)
{
#if defined FE_INVALID || defined FE_INEXACT
/* X < LONG_MAX + 1 implied by J0 < 31. */
if (sizeof (long int) == 4
&& x > (long double) LONG_MAX)
{
/* In the event of overflow we must raise the "invalid"
exception, but not "inexact". */
t = __nearbyintl (x);
feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
}
else
#endif
{
w = two63[sx] + x;
t = w - two63[sx];
}
GET_LDOUBLE_WORDS (se, i0, i1, t);
j0 = (se & 0x7fff) - 0x3fff;
result = (j0 < 0 ? 0 : i0 >> (31 - j0));
}
else if (j0 < (int32_t) (8 * sizeof (long int)) - 1)
{
if (j0 >= 63)
result = ((long int) i0 << (j0 - 31)) | (i1 << (j0 - 63));
else
{
#if defined FE_INVALID || defined FE_INEXACT
/* X < LONG_MAX + 1 implied by J0 < 63. */
if (sizeof (long int) == 8
&& x > (long double) LONG_MAX)
{
/* In the event of overflow we must raise the "invalid"
exception, but not "inexact". */
t = __nearbyintl (x);
feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
}
else
#endif
{
w = two63[sx] + x;
t = w - two63[sx];
}
GET_LDOUBLE_WORDS (se, i0, i1, t);
j0 = (se & 0x7fff) - 0x3fff;
if (j0 == 31)
result = (long int) i0;
else
result = ((long int) i0 << (j0 - 31)) | (i1 >> (63 - j0));
}
}
else
{
/* The number is too large. Unless it rounds to LONG_MIN,
FE_INVALID must be raised and the return value is
unspecified. */
#if defined FE_INVALID || defined FE_INEXACT
if (sizeof (long int) == 4
&& x < (long double) LONG_MIN
&& x > (long double) LONG_MIN - 1.0L)
{
/* If truncation produces LONG_MIN, the cast will not raise
the exception, but may raise "inexact". */
t = __nearbyintl (x);
feraiseexcept (t == LONG_MIN ? FE_INEXACT : FE_INVALID);
return LONG_MIN;
}
#endif
return (long int) x;
}
return sx ? -result : result;
}
libm_alias_ldouble (__lrint, lrint)
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