1 /* mpz_set_f (dest_integer, src_float) -- Assign DEST_INTEGER from SRC_FLOAT.
2
3 Copyright 1996, 2001, 2012, 2016 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
34 void
mpz_set_f(mpz_ptr w,mpf_srcptr u)35 mpz_set_f (mpz_ptr w, mpf_srcptr u)
36 {
37 mp_ptr wp, up;
38 mp_size_t size;
39 mp_exp_t exp;
40
41 /* abs(u)<1 truncates to zero */
42 exp = EXP (u);
43 if (exp <= 0)
44 {
45 SIZ(w) = 0;
46 return;
47 }
48
49 wp = MPZ_NEWALLOC (w, exp);
50 up = PTR(u);
51
52 size = SIZ (u);
53 SIZ(w) = (size >= 0 ? exp : -exp);
54 size = ABS (size);
55
56 if (exp > size)
57 {
58 /* pad with low zeros to get a total "exp" many limbs */
59 mp_size_t zeros = exp - size;
60 MPN_ZERO (wp, zeros);
61 wp += zeros;
62 }
63 else
64 {
65 /* exp<=size, truncate to the high "exp" many limbs */
66 up += (size - exp);
67 size = exp;
68 }
69
70 MPN_COPY (wp, up, size);
71 }
72