/* Round float value to long long int.

   Copyright (C) 1997-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   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>

#include <stdint.h>

#include <libm-alias-float.h>

/* Round to the nearest integer, with values exactly on a 0.5 boundary

   rounded away from zero, regardless of the current rounding mode.

   If (long long)x, when x is out of range of a long long, clips at

   LLONG_MAX or LLONG_MIN, then this implementation also clips.  */

long long int

__llroundf (float x)

{

  long long xr;

  if (HAVE_PPC_FCTIDZ)

    xr = (long long) x;

  else

    {

      float ax = fabsf (x);

      /* Avoid incorrect exceptions from libgcc conversions (as of GCC

	 5): <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59412>.  */

      if (ax < 0x1p31f)

	xr = (long long int) (long int) x;

      else if (!(ax < 0x1p55f))

	xr = (long long int) (long int) (x * 0x1p-32f) << 32;

      else

	{

	  uint32_t i0;

	  GET_FLOAT_WORD (i0, x);

	  int exponent = ((i0 >> 23) & 0xff) - 0x7f;

	  unsigned long long int mant = (i0 & 0x7fffff) | 0x800000;

	  mant <<= exponent - 23;

	  xr = (long long int) ((i0 & 0x80000000) != 0 ? -mant : mant);

	}

    }

  /* Avoid spurious "inexact" converting LLONG_MAX to float, and from

     subtraction when the result is out of range, by returning early

     for arguments large enough that no rounding is needed.  */

  if (!(fabsf (x) < 0x1p23f))

    return xr;

  float xrf = (float) xr;

  if (x >= 0.0)

    {

      if (x - xrf >= 0.5)

	xr += (long long) ((unsigned long long) xr + 1) > 0;

    }

  else

    {

      if (xrf - x >= 0.5)

	xr -= (long long) ((unsigned long long) xr - 1) < 0;

    }

  return xr;

}

libm_alias_float (__llround, llround)