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mpi-genesis             1 /* mpihelp-mul_3.c  -  MPI helper functions
mpi_second_cut          2  * Modified by No Such Labs. (C) 2015. See README.
mpi-genesis             3  *
mpi_second_cut          4  * This file was originally part of Gnu Privacy Guard (GPG), ver. 1.4.10,
mpi_second_cut          5  * SHA256(gnupg-1.4.10.tar.gz):
mpi_second_cut          6  *        0bfd74660a2f6cedcf7d8256db4a63c996ffebbcdc2cf54397bfb72878c5a85a
mpi_second_cut          7  * (C) 1994-2005 Free Software Foundation, Inc.
mpi-genesis             8  *
mpi_second_cut          9  * This program is free software: you can redistribute it and/or modify
mpi-genesis            10  * it under the terms of the GNU General Public License as published by
mpi_second_cut         11  * the Free Software Foundation, either version 3 of the License, or
mpi-genesis            12  * (at your option) any later version.
mpi-genesis            13  *
mpi_second_cut         14  * This program is distributed in the hope that it will be useful,
mpi-genesis            15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
mpi-genesis            16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
mpi-genesis            17  * GNU General Public License for more details.
mpi-genesis            18  *
mpi-genesis            19  * You should have received a copy of the GNU General Public License
mpi_second_cut         20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
mpi-genesis            21  */
mpi-genesis            22 
mpi-genesis            23 #include <stdio.h>
mpi-genesis            24 #include <stdlib.h>
mpi_second_cut         25 
mpi_second_cut         26 #include "knobs.h"
mpi-genesis            27 #include "mpi-internal.h"
mpi-genesis            28 #include "longlong.h"
mpi-genesis            29 
mpi-genesis            30 
mpi-genesis            31 mpi_limb_t
mpi-genesis            32 mpihelp_submul_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi-genesis            33 		  mpi_size_t s1_size, mpi_limb_t s2_limb)
mpi-genesis            34 {
mpi-genesis            35     mpi_limb_t cy_limb;
mpi-genesis            36     mpi_size_t j;
mpi-genesis            37     mpi_limb_t prod_high, prod_low;
mpi-genesis            38     mpi_limb_t x;
mpi-genesis            39 
mpi-genesis            40     /* The loop counter and index J goes from -SIZE to -1.  This way
mpi-genesis            41      * the loop becomes faster.  */
mpi-genesis            42     j = -s1_size;
mpi-genesis            43     res_ptr -= j;
mpi-genesis            44     s1_ptr -= j;
mpi-genesis            45 
mpi-genesis            46     cy_limb = 0;
mpi-genesis            47     do {
mpi-genesis            48 	umul_ppmm( prod_high, prod_low, s1_ptr[j], s2_limb);
mpi-genesis            49 
mpi-genesis            50 	prod_low += cy_limb;
mpi-genesis            51 	cy_limb = (prod_low < cy_limb?1:0) + prod_high;
mpi-genesis            52 
mpi-genesis            53 	x = res_ptr[j];
mpi-genesis            54 	prod_low = x - prod_low;
mpi-genesis            55 	cy_limb += prod_low > x?1:0;
mpi-genesis            56 	res_ptr[j] = prod_low;
mpi-genesis            57     } while( ++j );
mpi-genesis            58 
mpi-genesis            59     return cy_limb;
mpi-genesis            60 }
mpi-genesis            61 
mpi-genesis            62