Coverage Report

Created: 2025-03-06 06:58

/src/gmp/mpz/tdiv_qr.c
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/* mpz_tdiv_qr(quot,rem,dividend,divisor) -- Set QUOT to DIVIDEND/DIVISOR,
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   and REM to DIVIDEND mod DIVISOR.
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Copyright 1991, 1993, 1994, 2000, 2001, 2005, 2011, 2012, 2021 Free
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Software Foundation, 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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#include "longlong.h"
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void
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mpz_tdiv_qr (mpz_ptr quot, mpz_ptr rem, mpz_srcptr num, mpz_srcptr den)
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{
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  mp_size_t ql, n0;
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  mp_size_t ns, ds, nl, dl;
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  mp_ptr np, dp, qp, rp;
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  TMP_DECL;
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  ns = SIZ (num);
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  ds = SIZ (den);
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  nl = ABS (ns);
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  dl = ABS (ds);
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  ql = nl - dl + 1;
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  if (UNLIKELY (dl == 0))
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    DIVIDE_BY_ZERO;
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  rp = MPZ_REALLOC (rem, dl);
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  if (ql <= 0)
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    {
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      if (num != rem)
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  {
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    np = PTR (num);
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    MPN_COPY (rp, np, nl);
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    SIZ (rem) = SIZ (num);
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  }
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      /* This needs to follow the assignment to rem, in case the
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   numerator and quotient are the same.  */
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      SIZ (quot) = 0;
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      return;
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    }
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  qp = MPZ_REALLOC (quot, ql);
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  TMP_MARK;
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  np = PTR (num);
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  dp = PTR (den);
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  /* FIXME: We should think about how to handle the temporary allocation.
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     Perhaps mpn_tdiv_qr should handle it, since it anyway often needs to
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     allocate temp space.  */
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  /* Copy denominator to temporary space if it overlaps with the quotient
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     or remainder.  */
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  if (dp == rp || dp == qp)
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    {
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      mp_ptr tp;
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      tp = TMP_ALLOC_LIMBS (dl);
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      MPN_COPY (tp, dp, dl);
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      dp = tp;
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    }
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  /* Copy numerator to temporary space if it overlaps with the quotient or
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     remainder.  */
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  if (np == rp || np == qp)
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    {
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      mp_ptr tp;
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      tp = TMP_ALLOC_LIMBS (nl);
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      MPN_COPY (tp, np, nl);
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      np = tp;
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    }
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  for (n0 = 0; *dp == 0; ++dp)
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    {
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      rp [n0++] = *np++;
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      --nl;
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    }
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  mpn_tdiv_qr (qp, rp + n0, 0L, np, nl, dp, dl - n0);
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  ql -=  qp[ql - 1] == 0;
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  MPN_NORMALIZE (rp, dl);
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  SIZ (quot) = (ns ^ ds) >= 0 ? ql : -ql;
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  SIZ (rem) = ns >= 0 ? dl : -dl;
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  TMP_FREE;
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}