1/* Save current context.
2   Copyright (C) 2008-2016 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4   Contributed by David S. Miller <davem@davemloft.net>, 2008.
5
6   The GNU C Library is free software; you can redistribute it and/or
7   modify it under the terms of the GNU Lesser General Public
8   License as published by the Free Software Foundation; either
9   version 2.1 of the License, or (at your option) any later version.
10
11   The GNU C Library is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   Lesser General Public License for more details.
15
16   You should have received a copy of the GNU Lesser General Public
17   License along with the GNU C Library; if not, see
18   <http://www.gnu.org/licenses/>.  */
19
20#include <sysdep.h>
21
22#include "ucontext_i.h"
23
24/*  int __getcontext (ucontext_t *ucp)
25
26  Saves the machine context in UCP such that when it is activated,
27  it appears as if __getcontext() returned again.
28
29  This implementation is intended to be used for *synchronous* context
30  switches only.  Therefore, it does not have to save anything
31  other than the PRESERVED state.  */
32
33
34ENTRY(__getcontext)
35	save	%sp, -112, %sp
36	st	%g0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_PSR]
37
38	/* In reality, we only use the GREG_PC value when setting
39	   or swapping contexts.  But we fill in NPC for completeness.  */
40	add	%i7, 8, %o0
41	st	%o0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_PC]
42	add	%o0, 4, %o0
43	st	%o0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_NPC]
44
45	rd	%y, %o1
46	st	%o1, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_Y]
47
48	st	%g1, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G1]
49	st	%g2, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G2]
50	st	%g3, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G3]
51	st	%g4, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G4]
52	st	%g5, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G5]
53	st	%g6, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G6]
54	st	%g7, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G7]
55
56	mov	SIG_BLOCK, %o0
57	clr	%o1
58	add	%i0, UC_SIGMASK, %o2
59	mov	8, %o3
60	mov	__NR_rt_sigprocmask, %g1
61	ta	0x10
62
63	/* Zero, success, return value.  */
64	st	%g0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O0]
65	st	%i1, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O1]
66	st	%i2, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O2]
67	st	%i3, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O3]
68	st	%i4, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O4]
69	st	%i5, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O5]
70	st	%i6, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O6]
71	st	%i7, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O7]
72
73	st	%g0, [%i0 + UC_MCONTEXT + MC_GWINS]
74
75	/* Do not save FPU state, it is volatile across calls.  */
76	stb	%g0, [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_EN]
77
78	st	%g0, [%i0 + UC_MCONTEXT + MC_XRS + XRS_ID]
79	st	%g0, [%i0 + UC_MCONTEXT + MC_XRS + XRS_PTR]
80	jmpl	%i7 + 8, %g0
81	 restore %g0, %g0, %o0
82END(__getcontext)
83
84weak_alias (__getcontext, getcontext)
85