1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/* mpz_fdiv_ui -- Division rounding the quotient towards -infinity.
The remainder gets the same sign as the denominator.
Copyright 1994-1996, 2001, 2002, 2004, 2005, 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"
unsigned long int
mpz_fdiv_ui (mpz_srcptr dividend, unsigned long int divisor)
{
mp_size_t ns, nn;
mp_ptr np;
mp_limb_t rl;
if (UNLIKELY (divisor == 0))
DIVIDE_BY_ZERO;
ns = SIZ(dividend);
if (ns == 0)
{
return 0;
}
nn = ABS(ns);
np = PTR(dividend);
#if BITS_PER_ULONG > GMP_NUMB_BITS /* avoid warnings about shift amount */
if (divisor > GMP_NUMB_MAX)
{
mp_limb_t dp[2], rp[2];
mp_ptr qp;
mp_size_t rn;
TMP_DECL;
if (nn == 1) /* tdiv_qr requirements; tested above for 0 */
{
rl = np[0];
rp[0] = rl;
}
else
{
TMP_MARK;
dp[0] = divisor & GMP_NUMB_MASK;
dp[1] = divisor >> GMP_NUMB_BITS;
qp = TMP_ALLOC_LIMBS (nn - 2 + 1);
mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2);
TMP_FREE;
rl = rp[0] + (rp[1] << GMP_NUMB_BITS);
}
if (rl != 0 && ns < 0)
{
rl = divisor - rl;
rp[0] = rl & GMP_NUMB_MASK;
rp[1] = rl >> GMP_NUMB_BITS;
}
rn = 1 + (rl > GMP_NUMB_MAX); rn -= (rp[rn - 1] == 0);
}
else
#endif
{
rl = mpn_mod_1 (np, nn, (mp_limb_t) divisor);
if (rl == 0)
;
else
{
if (ns < 0)
rl = divisor - rl;
}
}
return rl;
}
|
