raw
smg_comms_c_wrappers    1 /* mpihelp-add_1.c  -  MPI helper functions
smg_comms_c_wrappers 2 * Modified by No Such Labs. (C) 2015. See README.
smg_comms_c_wrappers 3 *
smg_comms_c_wrappers 4 * This file was originally part of Gnu Privacy Guard (GPG), ver. 1.4.10,
smg_comms_c_wrappers 5 * SHA256(gnupg-1.4.10.tar.gz):
smg_comms_c_wrappers 6 * 0bfd74660a2f6cedcf7d8256db4a63c996ffebbcdc2cf54397bfb72878c5a85a
smg_comms_c_wrappers 7 * (C) 1994-2005 Free Software Foundation, Inc.
smg_comms_c_wrappers 8 *
smg_comms_c_wrappers 9 * This program is free software: you can redistribute it and/or modify
smg_comms_c_wrappers 10 * it under the terms of the GNU General Public License as published by
smg_comms_c_wrappers 11 * the Free Software Foundation, either version 3 of the License, or
smg_comms_c_wrappers 12 * (at your option) any later version.
smg_comms_c_wrappers 13 *
smg_comms_c_wrappers 14 * This program is distributed in the hope that it will be useful,
smg_comms_c_wrappers 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
smg_comms_c_wrappers 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
smg_comms_c_wrappers 17 * GNU General Public License for more details.
smg_comms_c_wrappers 18 *
smg_comms_c_wrappers 19 * You should have received a copy of the GNU General Public License
smg_comms_c_wrappers 20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
smg_comms_c_wrappers 21 */
smg_comms_c_wrappers 22
smg_comms_c_wrappers 23 #include <stdio.h>
smg_comms_c_wrappers 24 #include <stdlib.h>
smg_comms_c_wrappers 25
smg_comms_c_wrappers 26 #include "knobs.h"
smg_comms_c_wrappers 27 #include "mpi-internal.h"
smg_comms_c_wrappers 28 #include "longlong.h"
smg_comms_c_wrappers 29
smg_comms_c_wrappers 30 mpi_limb_t
smg_comms_c_wrappers 31 mpihelp_add_n( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
smg_comms_c_wrappers 32 mpi_ptr_t s2_ptr, mpi_size_t size)
smg_comms_c_wrappers 33 {
smg_comms_c_wrappers 34 mpi_limb_t x, y, cy;
smg_comms_c_wrappers 35 mpi_size_t j;
smg_comms_c_wrappers 36
smg_comms_c_wrappers 37 /* The loop counter and index J goes from -SIZE to -1. This way
smg_comms_c_wrappers 38 the loop becomes faster. */
smg_comms_c_wrappers 39 j = -size;
smg_comms_c_wrappers 40
smg_comms_c_wrappers 41 /* Offset the base pointers to compensate for the negative indices. */
smg_comms_c_wrappers 42 s1_ptr -= j;
smg_comms_c_wrappers 43 s2_ptr -= j;
smg_comms_c_wrappers 44 res_ptr -= j;
smg_comms_c_wrappers 45
smg_comms_c_wrappers 46 cy = 0;
smg_comms_c_wrappers 47 do {
smg_comms_c_wrappers 48 y = s2_ptr[j];
smg_comms_c_wrappers 49 x = s1_ptr[j];
smg_comms_c_wrappers 50 y += cy; /* add previous carry to one addend */
smg_comms_c_wrappers 51 cy = y < cy; /* get out carry from that addition */
smg_comms_c_wrappers 52 y += x; /* add other addend */
smg_comms_c_wrappers 53 cy += y < x; /* get out carry from that add, combine */
smg_comms_c_wrappers 54 res_ptr[j] = y;
smg_comms_c_wrappers 55 } while( ++j );
smg_comms_c_wrappers 56
smg_comms_c_wrappers 57 return cy;
smg_comms_c_wrappers 58 }
smg_comms_c_wrappers 59