1/* Swap to new context.
2   Copyright (C) 2008-2022 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library.  If not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#include <sysdep.h>
20#include "ucontext_i.h"
21
22	.text
23ENTRY(__swapcontext)
24
25	/* Copy rp to ret0 (r28).  */
26	copy %rp,%ret0
27
28	/* Create a frame.  */
29	ldo 64(%sp),%sp
30	.cfi_def_cfa_offset -64
31
32	/* Save the current machine context to oucp.  */
33	bl __getcontext,%rp
34
35	/* Copy oucp to register ret1 (r29).  __getcontext saves and
36	   restores it on a normal return.  It is restored from oR29
37	   on reactivation.  */
38	copy %r26,%ret1
39
40	/* Pop frame.  */
41	ldo -64(%sp),%sp
42	.cfi_def_cfa_offset 0
43
44	/* Load return pointer from oR28.  */
45	ldw oR28(%ret1),%rp
46
47	/* Return if error.  */
48	or,= %r0,%ret0,%r0
49	bv,n %r0(%rp)
50
51	/* Load sc_sar flag.  */
52	ldb oSAR(%ret1),%r20
53
54	/* Return if oucp context has been reactivated.  */
55	or,= %r0,%r20,%r0
56	bv,n %r0(%rp)
57
58	/* Mark sc_sar flag.  */
59	ldi 1,%r20
60	stb %r20,oSAR(%ret1)
61
62	/* Activate the machine context in ucp.  */
63	bl __setcontext,%rp
64	ldw oR25(%ret1),%r26
65
66	/* Load return pointer.  */
67	ldw oR28(%ret1),%rp
68	bv,n %r0(%rp)
69
70END(__swapcontext)
71
72weak_alias (__swapcontext, swapcontext)
73