Coverage Report

Created: 2024-11-21 07:03

/src/libgmp/mpz/fdiv_q_ui.c
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/* mpz_fdiv_q_ui -- Division rounding the quotient towards -infinity.
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   The remainder gets the same sign as the denominator.
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Copyright 1994-1996, 1999, 2001, 2002, 2004, 2012 Free Software Foundation,
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Inc.
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This file is part of the GNU MP Library.
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The GNU MP Library is free software; you can redistribute it and/or modify
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it under the terms of either:
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  * the GNU Lesser General Public License as published by the Free
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    Software Foundation; either version 3 of the License, or (at your
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    option) any later version.
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or
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  * the GNU General Public License as published by the Free Software
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    Foundation; either version 2 of the License, or (at your option) any
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    later version.
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or both in parallel, as here.
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The GNU MP Library is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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for more details.
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You should have received copies of the GNU General Public License and the
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GNU Lesser General Public License along with the GNU MP Library.  If not,
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see https://www.gnu.org/licenses/.  */
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#include "gmp-impl.h"
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unsigned long int
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mpz_fdiv_q_ui (mpz_ptr quot, mpz_srcptr dividend, unsigned long int divisor)
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{
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  mp_size_t ns, nn, qn;
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  mp_ptr np, qp;
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  mp_limb_t rl;
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  if (UNLIKELY (divisor == 0))
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    DIVIDE_BY_ZERO;
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  ns = SIZ(dividend);
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  if (ns == 0)
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    {
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      SIZ(quot) = 0;
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      return 0;
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0
    }
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  nn = ABS(ns);
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  qp = MPZ_REALLOC (quot, nn);
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  np = PTR(dividend);
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#if BITS_PER_ULONG > GMP_NUMB_BITS  /* avoid warnings about shift amount */
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  if (divisor > GMP_NUMB_MAX)
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    {
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      mp_limb_t dp[2], rp[2];
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      if (nn == 1)    /* tdiv_qr requirements; tested above for 0 */
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  {
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    qp[0] = 0;
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    rl = np[0];
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    qn = 1;   /* a white lie, fixed below */
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  }
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      else
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  {
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    dp[0] = divisor & GMP_NUMB_MASK;
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    dp[1] = divisor >> GMP_NUMB_BITS;
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    mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2);
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    rl = rp[0] + (rp[1] << GMP_NUMB_BITS);
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    qn = nn - 2 + 1;
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  }
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      if (rl != 0 && ns < 0)
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  {
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    mpn_incr_u (qp, (mp_limb_t) 1);
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    rl = divisor - rl;
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  }
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      qn -= qp[qn - 1] == 0; qn -= qn != 0 && qp[qn - 1] == 0;
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    }
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  else
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#endif
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    {
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      rl = mpn_divrem_1 (qp, (mp_size_t) 0, np, nn, (mp_limb_t) divisor);
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      if (rl != 0 && ns < 0)
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  {
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    mpn_incr_u (qp, (mp_limb_t) 1);
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    rl = divisor - rl;
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  }
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      qn = nn - (qp[nn - 1] == 0);
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    }
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  SIZ(quot) = ns >= 0 ? qn : -qn;
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  return rl;
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}