1/* double mpz_get_d_2exp (signed long int *exp, mpz_t src).
2
3Copyright 2001, 2003, 2004 Free Software Foundation, Inc.
4
5This file is part of the GNU MP Library.
6
7The GNU MP Library is free software; you can redistribute it and/or modify
8it under the terms of the GNU Lesser General Public License as published by
9the Free Software Foundation; either version 3 of the License, or (at your
10option) any later version.
11
12The GNU MP Library is distributed in the hope that it will be useful, but
13WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
15License for more details.
16
17You should have received a copy of the GNU Lesser General Public License
18along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
19
20#include "gmp.h"
21#include "gmp-impl.h"
22#include "longlong.h"
23
24double
25mpz_get_d_2exp (signed long int *exp2, mpz_srcptr src)
26{
27  mp_size_t size, abs_size;
28  mp_srcptr ptr;
29  int cnt;
30  long exp;
31
32  size = SIZ(src);
33  if (UNLIKELY (size == 0))
34    {
35      *exp2 = 0;
36      return 0.0;
37    }
38
39  ptr = PTR(src);
40  abs_size = ABS(size);
41  count_leading_zeros (cnt, ptr[abs_size - 1]);
42  exp = abs_size * GMP_NUMB_BITS - (cnt - GMP_NAIL_BITS);
43  *exp2 = exp;
44  return mpn_get_d (ptr, abs_size, size, -exp);
45}
46