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mpi-genesis             1 /* mpihelp-add_1.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_limb_t
mpi-genesis            31 mpihelp_add_n( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi-genesis            32 	       mpi_ptr_t s2_ptr, mpi_size_t size)
mpi-genesis            33 {
mpi-genesis            34     mpi_limb_t x, y, cy;
mpi-genesis            35     mpi_size_t j;
mpi-genesis            36 
mpi-genesis            37     /* The loop counter and index J goes from -SIZE to -1.  This way
mpi-genesis            38        the loop becomes faster.  */
mpi-genesis            39     j = -size;
mpi-genesis            40 
mpi-genesis            41     /* Offset the base pointers to compensate for the negative indices. */
mpi-genesis            42     s1_ptr -= j;
mpi-genesis            43     s2_ptr -= j;
mpi-genesis            44     res_ptr -= j;
mpi-genesis            45 
mpi-genesis            46     cy = 0;
mpi-genesis            47     do {
mpi-genesis            48 	y = s2_ptr[j];
mpi-genesis            49 	x = s1_ptr[j];
mpi-genesis            50 	y += cy;		  /* add previous carry to one addend */
mpi-genesis            51 	cy = y < cy;		  /* get out carry from that addition */
mpi-genesis            52 	y += x; 		  /* add other addend */
mpi-genesis            53 	cy += y < x;		  /* get out carry from that add, combine */
mpi-genesis            54 	res_ptr[j] = y;
mpi-genesis            55     } while( ++j );
mpi-genesis            56 
mpi-genesis            57     return cy;
mpi-genesis            58 }
mpi-genesis            59