/src/gmp-6.2.1/mpz/get_si.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* mpz_get_si(integer) -- Return the least significant digit from INTEGER. |
2 | | |
3 | | Copyright 1991, 1993-1995, 2000-2002, 2006, 2012 Free Software Foundation, Inc. |
4 | | |
5 | | This file is part of the GNU MP Library. |
6 | | |
7 | | The GNU MP Library is free software; you can redistribute it and/or modify |
8 | | it under the terms of either: |
9 | | |
10 | | * the GNU Lesser General Public License as published by the Free |
11 | | Software Foundation; either version 3 of the License, or (at your |
12 | | option) any later version. |
13 | | |
14 | | or |
15 | | |
16 | | * the GNU General Public License as published by the Free Software |
17 | | Foundation; either version 2 of the License, or (at your option) any |
18 | | later version. |
19 | | |
20 | | or both in parallel, as here. |
21 | | |
22 | | The GNU MP Library is distributed in the hope that it will be useful, but |
23 | | WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
24 | | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
25 | | for more details. |
26 | | |
27 | | You should have received copies of the GNU General Public License and the |
28 | | GNU Lesser General Public License along with the GNU MP Library. If not, |
29 | | see https://www.gnu.org/licenses/. */ |
30 | | |
31 | | #include "gmp-impl.h" |
32 | | |
33 | | signed long int |
34 | | mpz_get_si (mpz_srcptr z) __GMP_NOTHROW |
35 | 122 | { |
36 | 122 | mp_ptr zp = PTR (z); |
37 | 122 | mp_size_t size = SIZ (z); |
38 | 122 | mp_limb_t zl = zp[0]; |
39 | | |
40 | | #if GMP_NAIL_BITS != 0 |
41 | | if (ULONG_MAX > GMP_NUMB_MAX && ABS (size) >= 2) |
42 | | zl |= zp[1] << GMP_NUMB_BITS; |
43 | | #endif |
44 | | |
45 | 122 | if (size > 0) |
46 | 113 | return zl & LONG_MAX; |
47 | 9 | else if (size < 0) |
48 | | /* This expression is necessary to properly handle 0x80000000 */ |
49 | 0 | return -1 - (long) ((zl - 1) & LONG_MAX); |
50 | 9 | else |
51 | 9 | return 0; |
52 | 122 | } |