1/* Save and set current context. C-SKY ABIV2 version.
2 Copyright (C) 2018-2024 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
21#include "ucontext_i.h"
22
23/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */
24
25ENTRY (swapcontext)
26 /* Save params and lr. */
27 subi sp, 16
28 stw a0, (sp, 0)
29 stw a1, (sp, 4)
30 stw r15, (sp, 8)
31
32 /* Call getcontext. */
33#ifdef __PIC__
34 grs t1, .Lgetpc1
35.Lgetpc1:
36 lrw t0, .Lgetpc1@GOTPC
37 addu t1, t1, t0
38 lrw t0, __getcontext@GOT
39 ldr.w t0, (t1, t0 << 0)
40 jsr t0
41#else /* !__PIC__ */
42 jsri __getcontext
43#endif
44
45 mov a3, a0 /* Save return value. */
46
47 /* Restore params and lr. */
48 ldw a0, (sp, 0)
49 ldw a1, (sp, 4)
50 ldw r15, (sp, 8)
51 addi sp, 16
52
53 cmpnei a3, 0
54 bt error_exit
55
56 /* Fix up LR and the PC. */
57 stw sp, (a0, MCONTEXT_CSKY_SP)
58 stw r15, (a0, MCONTEXT_CSKY_LR)
59 stw r15, (a0, MCONTEXT_CSKY_PC)
60
61 /* Set setcontext's arg. */
62 mov a0, a1
63
64#ifdef __PIC__
65 grs t1, .Lgetpc2
66.Lgetpc2:
67 lrw a3, .Lgetpc2@GOTPC
68 addu t1, t1, a3
69 lrw a3, __setcontext@GOT
70 ldr.w a3, (t1, a3 << 0)
71#else /* __PIC__ */
72 lrw a3, __setcontext
73#endif /* __PIC__ */
74 jmp a3
75
76error_exit:
77 jmp r15
78END (swapcontext)
79

source code of glibc/sysdeps/unix/sysv/linux/csky/abiv2/swapcontext.S