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/* PowerPC-32 add_n -- Add two limb vectors of equal, non-zero length.
*
* Copyright (C) 1992, 1994, 1995, 1998 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
/*******************
* mpi_limb_t
* mpihelp_add_n( mpi_ptr_t res_ptr, (r3)
* mpi_ptr_t s1_ptr, (r4)
* mpi_ptr_t s2_ptr, (r5)
* mpi_size_t size) (r6)
*/
.toc
.extern mpihelp_add_n[DS]
.extern .mpihelp_add_n
.csect [PR]
.align 2
.globl mpihelp_add_n
.globl .mpihelp_add_n
.csect mpihelp_add_n[DS]
mpihelp_add_n:
.long .mpihelp_add_n, TOC[tc0], 0
.csect [PR]
.mpihelp_add_n:
mtctr 6 # copy size into CTR
lwz 8,0(4) # load least significant s1 limb
lwz 0,0(5) # load least significant s2 limb
addi 3,3,-4 # offset res_ptr, it's updated before used
addc 7,0,8 # add least significant limbs, set cy
bdz Lend # If done, skip loop
Loop: lwzu 8,4(4) # load s1 limb and update s1_ptr
lwzu 0,4(5) # load s2 limb and update s2_ptr
stwu 7,4(3) # store previous limb in load latency slot
adde 7,0,8 # add new limbs with cy, set cy
bdnz Loop # decrement CTR and loop back
Lend: stw 7,4(3) # store ultimate result limb
li 3,0 # load cy into ...
addze 3,3 # ... return value register
blr
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