Coverage Report

Created: 2024-11-21 07:03

/src/libgmp/mpz/rootrem.c
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/* mpz_rootrem(root, rem, u, nth) --  Set ROOT to trunc(U^(1/nth)) and
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   set REM to the remainder.
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Copyright 1999-2003, 2005, 2012 Free 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 <stdio.h>    /* for NULL */
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#include "gmp-impl.h"
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void
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mpz_rootrem (mpz_ptr root, mpz_ptr rem, mpz_srcptr u, unsigned long int nth)
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{
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  mp_ptr rootp, up, remp;
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  mp_size_t us, un, rootn, remn;
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  TMP_DECL;
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  us = SIZ(u);
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  /* even roots of negatives provoke an exception */
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  if (UNLIKELY (us < 0 && (nth & 1) == 0))
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0
    SQRT_OF_NEGATIVE;
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  /* root extraction interpreted as c^(1/nth) means a zeroth root should
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     provoke a divide by zero, do this even if c==0 */
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  if (UNLIKELY (nth == 0))
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    DIVIDE_BY_ZERO;
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  if (us == 0)
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1
    {
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1
      if (root != NULL)
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1
  SIZ(root) = 0;
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1
      SIZ(rem) = 0;
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1
      return;
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1
    }
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  un = ABS (us);
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  rootn = (un - 1) / nth + 1;
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  TMP_MARK;
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  /* FIXME: Perhaps disallow root == NULL */
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  if (root != NULL && u != root)
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    rootp = MPZ_NEWALLOC (root, rootn);
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0
  else
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    rootp = TMP_ALLOC_LIMBS (rootn);
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  if (u != rem)
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    remp = MPZ_NEWALLOC (rem, un);
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  else
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    remp = TMP_ALLOC_LIMBS (un);
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  up = PTR(u);
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  if (nth == 1)
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1
    {
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      MPN_COPY (rootp, up, un);
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      remn = 0;
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1
    }
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  else
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    {
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      remn = mpn_rootrem (rootp, remp, up, un, (mp_limb_t) nth);
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    }
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  if (root != NULL)
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    {
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      SIZ(root) = us >= 0 ? rootn : -rootn;
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      if (u == root)
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  MPN_COPY (up, rootp, rootn);
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    }
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  if (u == rem)
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    MPN_COPY (up, remp, remn);
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  SIZ(rem) = us >= 0 ? remn : -remn;
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  TMP_FREE;
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}