1/* SPARC v9 __mpn_rshift --
2
3   Copyright (C) 1996-2022 Free Software Foundation, Inc.
4
5   This file is part of the GNU MP Library.
6
7   The GNU MP Library is free software; you can redistribute it and/or modify
8   it under the terms of the GNU Lesser General Public License as published by
9   the Free Software Foundation; either version 2.1 of the License, or (at your
10   option) any later version.
11
12   The GNU MP Library is distributed in the hope that it will be useful, but
13   WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
15   License for more details.
16
17   You should have received a copy of the GNU Lesser General Public License
18   along with the GNU MP Library; see the file COPYING.LIB.  If not,
19   see <https://www.gnu.org/licenses/>.  */
20
21#include <sysdep.h>
22
23/* INPUT PARAMETERS
24   res_ptr	%o0
25   src_ptr	%o1
26   size		%o2
27   cnt		%o3  */
28
29	.register	%g2, #scratch
30	.register	%g3, #scratch
31
32ENTRY(__mpn_rshift)
33	ldx	[%o1],%g2	! load first limb
34	sub	%g0,%o3,%o5	! negate shift count
35	add	%o2,-1,%o2
36	andcc	%o2,4-1,%g4	! number of limbs in first loop
37	sllx	%g2,%o5,%g1	! compute function result
38	be,pn	%xcc,.L0	! if multiple of 4 limbs, skip first loop
39	 mov	%g1,%g5
40
41	sub	%o2,%g4,%o2	! adjust count for main loop
42
43.Loop0:	ldx	[%o1+8],%g3
44	add	%o0,8,%o0
45	add	%o1,8,%o1
46	srlx	%g2,%o3,%o4
47	addcc	%g4,-1,%g4
48	sllx	%g3,%o5,%g1
49	mov	%g3,%g2
50	or	%o4,%g1,%o4
51	bne,pt	%xcc,.Loop0
52	 stx	%o4,[%o0-8]
53
54.L0:	brz,pn	%o2,.Lend
55	 nop
56
57.Loop:	ldx	[%o1+8],%g3
58	add	%o0,32,%o0
59	srlx	%g2,%o3,%o4
60	addcc	%o2,-4,%o2
61	sllx	%g3,%o5,%g1
62
63	ldx	[%o1+16],%g2
64	srlx	%g3,%o3,%g4
65	or	%o4,%g1,%o4
66	stx	%o4,[%o0-32]
67	sllx	%g2,%o5,%g1
68
69	ldx	[%o1+24],%g3
70	srlx	%g2,%o3,%o4
71	or	%g4,%g1,%g4
72	stx	%g4,[%o0-24]
73	sllx	%g3,%o5,%g1
74
75	ldx	[%o1+32],%g2
76	srlx	%g3,%o3,%g4
77	or	%o4,%g1,%o4
78	stx	%o4,[%o0-16]
79	sllx	%g2,%o5,%g1
80
81	add	%o1,32,%o1
82	or	%g4,%g1,%g4
83	bne,pt	%xcc,.Loop
84	 stx	%g4,[%o0-8]
85
86.Lend:	srlx	%g2,%o3,%g2
87	stx	%g2,[%o0-0]
88
89	jmpl	%o7+8,%g0
90	 mov	%g5,%o0
91
92END(__mpn_rshift)
93