1/* Add two limb vectors of the same length > 0 and store sum in a third
2   limb vector.
3   Copyright (C) 2001-2022 Free Software Foundation, Inc.
4   This file is part of the GNU MP Library.
5
6   The GNU MP Library is free software; you can redistribute it and/or modify
7   it under the terms of the GNU Lesser General Public License as published by
8   the Free Software Foundation; either version 2.1 of the License, or (at your
9   option) any later version.
10
11   The GNU MP Library is distributed in the hope that it will be useful, but
12   WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
14   License for more details.
15
16   You should have received a copy of the GNU Lesser General Public License
17   along with the GNU MP Library; see the file COPYING.LIB.  If not,
18   see <https://www.gnu.org/licenses/>.  */
19
20/*
21   INPUT PARAMETERS
22   res_ptr	%r2
23   s1_ptr	%r3
24   s2_ptr	%r4
25   size		%r5
26*/
27
28#include "sysdep.h"
29#include "asm-syntax.h"
30
31	.text
32ENTRY(__mpn_add_n)
33	stg    %r6,48(%r15)   # save register 6
34	cfi_offset (%r6,-112)
35	slgr   %r1,%r1
36        lghi   %r0,1          # cannot use ahi to add carry, use alr
37.L0:	lg     %r6,0(%r1,%r3) # .L0 -> no carry from last add
38	alg    %r6,0(%r1,%r4)
39	stg    %r6,0(%r1,%r2)
40	la     %r1,8(%r1)
41	brc    3,.L3
42.L1:	brct   %r5,.L0
43	slgr   %r2,%r2        # no last carry to return
44	j      .Lexit
45.L2:    lg     %r6,0(%r1,%r3) # .L2 -> carry from last add
46	alg    %r6,0(%r1,%r4)
47	brc    3,.L4
48	algr   %r6,%r0        # no carry yet, add carry from last add
49	stg    %r6,0(%r1,%r2)
50	la     %r1,8(%r1)
51	brc    12,.L1          # new carry ?
52.L3:	brct   %r5,.L2
53	lgr    %r2,%r0        # return last carry
54	j      .Lexit
55.L4:	algr   %r6,%r0        # already a carry, add carry from last add
56	stg    %r6,0(%r1,%r2)
57	la     %r1,8(%r1)
58	brct   %r5,.L2
59	lgr    %r2,%r0        # return last carry
60.Lexit:	lg     %r6,48(%r15)   # restore register 6
61	br     %r14
62END(__mpn_add_n)
63