1/* double mpf_get_d_2exp (signed long int *exp, mpf_t src).
2
3Copyright 2001, 2002, 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
24
25double
26mpf_get_d_2exp (signed long int *exp2, mpf_srcptr src)
27{
28  mp_size_t size, abs_size;
29  mp_srcptr ptr;
30  int cnt;
31  long exp;
32
33  size = SIZ(src);
34  if (UNLIKELY (size == 0))
35    {
36      *exp2 = 0;
37      return 0.0;
38    }
39
40  ptr = PTR(src);
41  abs_size = ABS (size);
42  count_leading_zeros (cnt, ptr[abs_size - 1]);
43  cnt -= GMP_NAIL_BITS;
44
45  exp = EXP(src) * GMP_NUMB_BITS - cnt;
46  *exp2 = exp;
47
48  return mpn_get_d (ptr, abs_size, (mp_size_t) 0,
49                    (long) - (abs_size * GMP_NUMB_BITS - cnt));
50}
51