/* 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.

   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 <fenv.h>

#include <limits.h>

#include <math.h>

#include <math-narrow-eval.h>

#include <math_private.h>

#include <libm-alias-double.h>

#include <fix-fp-int-convert-overflow.h>

static const double two52[2] =

{

  4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */

 -4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */

};

long long int

__llrint (double x)

{

  int32_t j0;

  uint32_t i1, i0;

  long long int result;

  double w;

  double t;

  int sx;

  EXTRACT_WORDS (i0, i1, x);

  j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;

  sx = i0 >> 31;

  i0 &= 0xfffff;

  i0 |= 0x100000;

  if (j0 < 20)

    {

      w = math_narrow_eval (two52[sx] + x);

      t = w - two52[sx];

      EXTRACT_WORDS (i0, i1, t);

      j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;

      i0 &= 0xfffff;

      i0 |= 0x100000;

      result = (j0 < 0 ? 0 : 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

	{

	  w = math_narrow_eval (two52[sx] + x);

	  t = w - two52[sx];

	  EXTRACT_WORDS (i0, i1, t);

	  j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;

	  i0 &= 0xfffff;

	  i0 |= 0x100000;

	  if (j0 == 20)

	    result = (long long int) i0;

	  else

	    result = ((long long int) i0 << (j0 - 20)) | (i1 >> (52 - j0));

	}

    }

  else

    {

#ifdef FE_INVALID

      /* The number is too large.  Unless it rounds to LLONG_MIN,

	 FE_INVALID must be raised and the return value is

	 unspecified.  */

      if (FIX_DBL_LLONG_CONVERT_OVERFLOW && x != (double) LLONG_MIN)

	{

	  feraiseexcept (FE_INVALID);

	  return sx == 0 ? LLONG_MAX : LLONG_MIN;

	}

#endif

      return (long long int) x;

    }

  return sx ? -result : result;

}

libm_alias_double (__llrint, llrint)