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- /* Round double value to long long int.
- Copyright (C) 1997 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"
- long long int
- llround (double x)
- {
- int32_t _j0;
- u_int32_t i1, i0;
- long long int result;
- int sign;
- EXTRACT_WORDS (i0, i1, x);
- _j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
- sign = (i0 & 0x80000000) != 0 ? -1 : 1;
- i0 &= 0xfffff;
- i0 |= 0x100000;
- if (_j0 < 20)
- {
- if (_j0 < 0)
- return _j0 < -1 ? 0 : sign;
- else
- {
- i0 += 0x80000 >> _j0;
- result = i0 >> (20 - _j0);
- }
- }
- else if (_j0 < (int32_t) (8 * sizeof (long long int)) - 1)
- {
- if (_j0 >= 52)
- result = (((long long int) i0 << 32) | i1) << (_j0 - 52);
- else
- {
- u_int32_t j = i1 + (0x80000000 >> (_j0 - 20));
- if (j < i1)
- ++i0;
- if (_j0 == 20)
- result = (long long int) i0;
- else
- result = ((long long int) i0 << (_j0 - 20)) | (j >> (52 - _j0));
- }
- }
- else
- {
- /* The number is too large. It is left implementation defined
- what happens. */
- return (long long int) x;
- }
- return sign * result;
- }
- libm_hidden_def(llround)
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