1 /* mpn_preinv_mod_1 (up, un, d, dinv) -- Divide (UP,,UN) by the normalized D. 2 DINV should be 2^(2*GMP_LIMB_BITS) / D - 2^GMP_LIMB_BITS. 3 Return the single-limb remainder. 4 5 Copyright 1991, 1993, 1994, 2000, 2001, 2002, 2004, 2005 Free Software 6 Foundation, Inc. 7 8 This file is part of the GNU MP Library. 9 10 The GNU MP Library is free software; you can redistribute it and/or modify it 11 under the terms of the GNU Lesser General Public License as published by the 12 Free Software Foundation; either version 3 of the License, or (at your 13 option) any later version. 14 15 The GNU MP Library is distributed in the hope that it will be useful, but 16 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License 18 for more details. 19 20 You should have received a copy of the GNU Lesser General Public License along 21 with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 22 23 #include "gmp.h" 24 #include "gmp-impl.h" 25 #include "longlong.h" 26 27 28 /* This function used to be documented, but is now considered obsolete. It 29 continues to exist for binary compatibility, even when not required 30 internally. */ 31 32 mp_limb_t 33 mpn_preinv_mod_1 (mp_srcptr up, mp_size_t un, mp_limb_t d, mp_limb_t dinv) 34 { 35 mp_size_t i; 36 mp_limb_t n0, r; 37 mp_limb_t dummy; 38 39 ASSERT (un >= 1); 40 ASSERT (d & GMP_LIMB_HIGHBIT); 41 42 r = up[un - 1]; 43 if (r >= d) 44 r -= d; 45 46 for (i = un - 2; i >= 0; i--) 47 { 48 n0 = up[i]; 49 udiv_qrnnd_preinv (dummy, r, r, n0, d, dinv); 50 } 51 return r; 52 } 53