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/* Round argument to nearest integral value according to current rounding
direction.
Copyright (C) 1997-2018 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 "quadmath-imp.h"
static const __float128 two112[2] =
{
5.19229685853482762853049632922009600E+33Q, /* 0x406F000000000000, 0 */
-5.19229685853482762853049632922009600E+33Q /* 0xC06F000000000000, 0 */
};
long int
lrintq (__float128 x)
{
int32_t j0;
uint64_t i0,i1;
__float128 w;
__float128 t;
long int result;
int sx;
GET_FLT128_WORDS64 (i0, i1, x);
j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
sx = i0 >> 63;
i0 &= 0x0000ffffffffffffLL;
i0 |= 0x0001000000000000LL;
if (j0 < (int32_t) (8 * sizeof (long int)) - 1)
{
if (j0 < 48)
{
#if defined FE_INVALID || defined FE_INEXACT
/* X < LONG_MAX + 1 implied by J0 < 31. */
if (sizeof (long int) == 4
&& x > (__float128) LONG_MAX)
{
/* In the event of overflow we must raise the "invalid"
exception, but not "inexact". */
t = nearbyintq (x);
feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
}
else
#endif
{
w = two112[sx] + x;
t = w - two112[sx];
}
GET_FLT128_WORDS64 (i0, i1, t);
j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
i0 &= 0x0000ffffffffffffLL;
i0 |= 0x0001000000000000LL;
result = (j0 < 0 ? 0 : i0 >> (48 - j0));
}
else if (j0 >= 112)
result = ((long int) i0 << (j0 - 48)) | (i1 << (j0 - 112));
else
{
#if defined FE_INVALID || defined FE_INEXACT
/* X < LONG_MAX + 1 implied by J0 < 63. */
if (sizeof (long int) == 8
&& x > (__float128) LONG_MAX)
{
/* In the event of overflow we must raise the "invalid"
exception, but not "inexact". */
t = nearbyintq (x);
feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID);
}
else
#endif
{
w = two112[sx] + x;
t = w - two112[sx];
}
GET_FLT128_WORDS64 (i0, i1, t);
j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
i0 &= 0x0000ffffffffffffLL;
i0 |= 0x0001000000000000LL;
if (j0 == 48)
result = (long int) i0;
else
result = ((long int) i0 << (j0 - 48)) | (i1 >> (112 - 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 (x < (__float128) LONG_MIN
&& x > (__float128) LONG_MIN - 1)
{
/* If truncation produces LONG_MIN, the cast will not raise
the exception, but may raise "inexact". */
t = nearbyintq (x);
feraiseexcept (t == LONG_MIN ? FE_INEXACT : FE_INVALID);
return LONG_MIN;
}
else if (FIX_FLT128_LONG_CONVERT_OVERFLOW && x != (__float128) LONG_MIN)
{
feraiseexcept (FE_INVALID);
return sx == 0 ? LONG_MAX : LONG_MIN;
}
#endif
return (long int) x;
}
return sx ? -result : result;
}
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