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/* mpz_set_d(integer, val) -- Assign INTEGER with a double value VAL.

Copyright (C) 1995 Free Software Foundation, Inc.

This file is part of the GNU MP Library.

The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.

The GNU MP 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 Library General Public
License for more details.

You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */

#include "gmp.h"
#include "gmp-impl.h"

void
#if __STDC__
mpz_set_d (mpz_ptr r, double d)
#else
mpz_set_d (r, d)
     mpz_ptr r;
     double d;
#endif
{
  int negative;
  mp_size_t size;
  mp_limb_t tp[3];
  mp_ptr rp;

  negative = d < 0;
  d = ABS (d);

  /* Handle small arguments quickly.  */
  if (d < MP_BASE_AS_DOUBLE)
    {
      mp_limb_t tmp;
      tmp = d;
      PTR(r)[0] = tmp;
      SIZ(r) = negative ? -(tmp != 0) : (tmp != 0);
      return;
    }

  size = __gmp_extract_double (tp, d);

  if (ALLOC(r) < size)
    _mpz_realloc (r, size);

  rp = PTR (r);

#if BITS_PER_MP_LIMB == 32
  switch (size)
    {
    default:
      MPN_ZERO (rp, size - 3);
      rp += size - 3;
    case 3:
      rp[2] = tp[2];
      rp[1] = tp[1];
      rp[0] = tp[0];
      break;
    case 2:
      rp[1] = tp[2];
      rp[0] = tp[1];
      break;
    case 1:
      abort ();
    }
#else
  switch (size)
    {
    default:
      MPN_ZERO (rp, size - 2);
      rp += size - 2;
    case 2:
      rp[1] = tp[1];
      rp[0] = tp[0];
      break;
    case 1:
      abort ();
    }
#endif

  SIZ(r) = negative ? -size : size;
}