1*86d7f5d3SJohn Marino /* mpn_bdiv_dbm1c -- divide an mpn number by a divisor of B-1, where B is the
2*86d7f5d3SJohn Marino limb base. The dbm1c moniker means "Divisor of B Minus 1 with Carry".
3*86d7f5d3SJohn Marino
4*86d7f5d3SJohn Marino THE FUNCTION IN THIS FILE IS INTERNAL WITH A MUTABLE INTERFACE. IT IS ONLY
5*86d7f5d3SJohn Marino SAFE TO REACH IT THROUGH DOCUMENTED INTERFACES. IN FACT, IT IS ALMOST
6*86d7f5d3SJohn Marino GUARANTEED THAT IT'LL CHANGE OR DISAPPEAR IN A FUTURE GNU MP RELEASE.
7*86d7f5d3SJohn Marino
8*86d7f5d3SJohn Marino Copyright 2008, 2009 Free Software Foundation, Inc.
9*86d7f5d3SJohn Marino
10*86d7f5d3SJohn Marino This file is part of the GNU MP Library.
11*86d7f5d3SJohn Marino
12*86d7f5d3SJohn Marino The GNU MP Library is free software; you can redistribute it and/or modify
13*86d7f5d3SJohn Marino it under the terms of the GNU Lesser General Public License as published by
14*86d7f5d3SJohn Marino the Free Software Foundation; either version 3 of the License, or (at your
15*86d7f5d3SJohn Marino option) any later version.
16*86d7f5d3SJohn Marino
17*86d7f5d3SJohn Marino The GNU MP Library is distributed in the hope that it will be useful, but
18*86d7f5d3SJohn Marino WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
19*86d7f5d3SJohn Marino or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
20*86d7f5d3SJohn Marino License for more details.
21*86d7f5d3SJohn Marino
22*86d7f5d3SJohn Marino You should have received a copy of the GNU Lesser General Public License
23*86d7f5d3SJohn Marino along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
24*86d7f5d3SJohn Marino
25*86d7f5d3SJohn Marino #include "gmp.h"
26*86d7f5d3SJohn Marino #include "gmp-impl.h"
27*86d7f5d3SJohn Marino #include "longlong.h"
28*86d7f5d3SJohn Marino
29*86d7f5d3SJohn Marino
30*86d7f5d3SJohn Marino mp_limb_t
mpn_bdiv_dbm1c(mp_ptr qp,mp_srcptr ap,mp_size_t n,mp_limb_t bd,mp_limb_t h)31*86d7f5d3SJohn Marino mpn_bdiv_dbm1c (mp_ptr qp, mp_srcptr ap, mp_size_t n, mp_limb_t bd, mp_limb_t h)
32*86d7f5d3SJohn Marino {
33*86d7f5d3SJohn Marino mp_limb_t a, p0, p1, cy;
34*86d7f5d3SJohn Marino mp_size_t i;
35*86d7f5d3SJohn Marino
36*86d7f5d3SJohn Marino for (i = 0; i < n; i++)
37*86d7f5d3SJohn Marino {
38*86d7f5d3SJohn Marino a = ap[i];
39*86d7f5d3SJohn Marino umul_ppmm (p1, p0, a, bd << GMP_NAIL_BITS);
40*86d7f5d3SJohn Marino p0 >>= GMP_NAIL_BITS;
41*86d7f5d3SJohn Marino cy = h < p0;
42*86d7f5d3SJohn Marino h = (h - p0) & GMP_NUMB_MASK;
43*86d7f5d3SJohn Marino qp[i] = h;
44*86d7f5d3SJohn Marino h = h - p1 - cy;
45*86d7f5d3SJohn Marino }
46*86d7f5d3SJohn Marino
47*86d7f5d3SJohn Marino return h;
48*86d7f5d3SJohn Marino }
49