1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
/* Copyright (C) 2002-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <features.h>
#include "ucontext_i.h"
/* __swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
Saves the machine context in oucp such that when it is activated,
it appears as if __swapcontext() returned again, restores the
machine context in ucp and thereby resumes execution in that
context.
This implementation is intended to be used for *synchronous* context
switches only. Therefore, it does not have to save anything
other than the PRESERVED state. */
ENTRY(__swapcontext)
/* While not part of the ABI a system call never clobbers r0
or r1. So keeping the values here while calling
rt_sigprocmask is ok. */
lgr %r1,%r2
lgr %r0,%r3
/* Store fpu context. */
stfpc SC_FPC(%r1)
std %f0,SC_FPRS(%r1)
std %f1,SC_FPRS+8(%r1)
std %f2,SC_FPRS+16(%r1)
std %f3,SC_FPRS+24(%r1)
std %f4,SC_FPRS+32(%r1)
std %f5,SC_FPRS+40(%r1)
std %f6,SC_FPRS+48(%r1)
std %f7,SC_FPRS+56(%r1)
std %f8,SC_FPRS+64(%r1)
std %f9,SC_FPRS+72(%r1)
std %f10,SC_FPRS+80(%r1)
std %f11,SC_FPRS+88(%r1)
std %f12,SC_FPRS+96(%r1)
std %f13,SC_FPRS+104(%r1)
std %f14,SC_FPRS+112(%r1)
std %f15,SC_FPRS+120(%r1)
/* Set __swapcontext return value to 0. */
slgr %r2,%r2
/* Store access registers. */
stam %a0,%a15,SC_ACRS(%r1)
/* Store general purpose registers. */
stmg %r0,%r15,SC_GPRS(%r1)
/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask,
sigsetsize). */
la %r2,SIG_SETMASK
lgr %r5,%r0
la %r3,SC_MASK(%r5)
la %r4,SC_MASK(%r1)
lghi %r5,_NSIG8
svc SYS_ify(rt_sigprocmask)
/* Load fpu context. */
lgr %r5,%r0
lfpc SC_FPC(%r5)
ld %f0,SC_FPRS(%r5)
ld %f1,SC_FPRS+8(%r5)
ld %f2,SC_FPRS+16(%r5)
ld %f3,SC_FPRS+24(%r5)
ld %f4,SC_FPRS+32(%r5)
ld %f5,SC_FPRS+40(%r5)
ld %f6,SC_FPRS+48(%r5)
ld %f7,SC_FPRS+56(%r5)
ld %f8,SC_FPRS+64(%r5)
ld %f9,SC_FPRS+72(%r5)
ld %f10,SC_FPRS+80(%r5)
ld %f11,SC_FPRS+88(%r5)
ld %f12,SC_FPRS+96(%r5)
ld %f13,SC_FPRS+104(%r5)
ld %f14,SC_FPRS+112(%r5)
ld %f15,SC_FPRS+120(%r5)
/* Don't touch %a0 and %a1, used for thread purposes. */
lam %a2,%a15,SC_ACRS+8(%r5)
/* Load general purpose registers. */
lmg %r0,%r15,SC_GPRS(%r5)
/* Return. */
br %r14
END(__swapcontext)
weak_alias (__swapcontext, swapcontext)
|
