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/* mpf_div_ui -- Divide a float with an unsigned integer.

Copyright 1993, 1994, 1996, 2000-2002, 2004, 2005, 2012 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 Lesser General Public License as published
by the Free Software Foundation; either version 3 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library.  If not, see https://www.gnu.org/licenses/.  */

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

void
mpf_div_ui (mpf_ptr r, mpf_srcptr u, unsigned long int v)
{
  mp_srcptr up;
  mp_ptr rp, tp, rtp;
  mp_size_t usize;
  mp_size_t rsize, tsize;
  mp_size_t sign_quotient;
  mp_size_t prec;
  mp_limb_t q_limb;
  mp_exp_t rexp;
  TMP_DECL;

#if BITS_PER_ULONG > GMP_NUMB_BITS  /* avoid warnings about shift amount */
  if (v > GMP_NUMB_MAX)
    {
      mpf_t vf;
      mp_limb_t vl[2];
      SIZ(vf) = 2;
      EXP(vf) = 2;
      PTR(vf) = vl;
      vl[0] = v & GMP_NUMB_MASK;
      vl[1] = v >> GMP_NUMB_BITS;
      mpf_div (r, u, vf);
      return;
    }
#endif

  if (UNLIKELY (v == 0))
    DIVIDE_BY_ZERO;

  usize = u->_mp_size;

  if (usize == 0)
    {
      r->_mp_size = 0;
      r->_mp_exp = 0;
      return;
    }

  sign_quotient = usize;
  usize = ABS (usize);
  prec = r->_mp_prec;

  TMP_MARK;

  rp = r->_mp_d;
  up = u->_mp_d;

  tsize = 1 + prec;
  tp = TMP_ALLOC_LIMBS (tsize + 1);

  if (usize > tsize)
    {
      up += usize - tsize;
      usize = tsize;
      rtp = tp;
    }
  else
    {
      MPN_ZERO (tp, tsize - usize);
      rtp = tp + (tsize - usize);
    }

  /* Move the dividend to the remainder.  */
  MPN_COPY (rtp, up, usize);

  mpn_divmod_1 (rp, tp, tsize, (mp_limb_t) v);
  q_limb = rp[tsize - 1];

  rsize = tsize - (q_limb == 0);
  rexp = u->_mp_exp - (q_limb == 0);
  r->_mp_size = sign_quotient >= 0 ? rsize : -rsize;
  r->_mp_exp = rexp;
  TMP_FREE;
}