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/* double mpz_get_d_2exp (signed long int *exp, mpz_t src).

Copyright 2001, 2003, 2004, 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"

double
mpz_get_d_2exp (signed long int *exp2, mpz_srcptr src)
{
  mp_size_t size, abs_size;
  mp_srcptr ptr;
  long exp;

  size = SIZ(src);
  if (UNLIKELY (size == 0))
    {
      *exp2 = 0;
      return 0.0;
    }

  ptr = PTR(src);
  abs_size = ABS(size);
  MPN_SIZEINBASE_2EXP(exp, ptr, abs_size, 1);
  *exp2 = exp;
  return mpn_get_d (ptr, abs_size, size, -exp);
}