1/* Save and set current context.
2 Copyright (C) 2009-2022 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 "ucontext-macros.h"
20
21/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */
22
23LEAF (__swapcontext)
24 mv t0, a1 /* Save ucp into t0. */
25
26 SAVE_INT_REG (ra, 0, a0)
27 SAVE_INT_REG (ra, 1, a0)
28 SAVE_INT_REG (sp, 2, a0)
29 SAVE_INT_REG (s0, 8, a0)
30 SAVE_INT_REG (s1, 9, a0)
31 SAVE_INT_REG (x0, 10, a0) /* return 0 by overwriting a0. */
32 SAVE_INT_REG (s2, 18, a0)
33 SAVE_INT_REG (s3, 19, a0)
34 SAVE_INT_REG (s4, 20, a0)
35 SAVE_INT_REG (s5, 21, a0)
36 SAVE_INT_REG (s6, 22, a0)
37 SAVE_INT_REG (s7, 23, a0)
38 SAVE_INT_REG (s8, 24, a0)
39 SAVE_INT_REG (s9, 25, a0)
40 SAVE_INT_REG (s10, 26, a0)
41 SAVE_INT_REG (s11, 27, a0)
42
43#ifndef __riscv_float_abi_soft
44 frsr a1
45
46 SAVE_FP_REG (fs0, 8, a0)
47 SAVE_FP_REG (fs1, 9, a0)
48 SAVE_FP_REG (fs2, 18, a0)
49 SAVE_FP_REG (fs3, 19, a0)
50 SAVE_FP_REG (fs4, 20, a0)
51 SAVE_FP_REG (fs5, 21, a0)
52 SAVE_FP_REG (fs6, 22, a0)
53 SAVE_FP_REG (fs7, 23, a0)
54 SAVE_FP_REG (fs8, 24, a0)
55 SAVE_FP_REG (fs9, 25, a0)
56 SAVE_FP_REG (fs10, 26, a0)
57 SAVE_FP_REG (fs11, 27, a0)
58
59 sw a1, MCONTEXT_FSR(a0)
60#endif /* __riscv_float_abi_soft */
61
62/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask, _NSIG8) */
63 li a3, _NSIG8
64 add a2, a0, UCONTEXT_SIGMASK
65 add a1, t0, UCONTEXT_SIGMASK
66 li a0, SIG_SETMASK
67
68 li a7, SYS_ify (rt_sigprocmask)
69 scall
70
71 bltz a0, 99f
72
73#ifndef __riscv_float_abi_soft
74 lw t1, MCONTEXT_FSR(t0)
75
76 RESTORE_FP_REG (fs0, 8, t0)
77 RESTORE_FP_REG (fs1, 9, t0)
78 RESTORE_FP_REG (fs2, 18, t0)
79 RESTORE_FP_REG (fs3, 19, t0)
80 RESTORE_FP_REG (fs4, 20, t0)
81 RESTORE_FP_REG (fs5, 21, t0)
82 RESTORE_FP_REG (fs6, 22, t0)
83 RESTORE_FP_REG (fs7, 23, t0)
84 RESTORE_FP_REG (fs8, 24, t0)
85 RESTORE_FP_REG (fs9, 25, t0)
86 RESTORE_FP_REG (fs10, 26, t0)
87 RESTORE_FP_REG (fs11, 27, t0)
88
89 fssr t1
90#endif /* __riscv_float_abi_soft */
91
92 /* Note the contents of argument registers will be random
93 unless makecontext() has been called. */
94 RESTORE_INT_REG (t1, 0, t0)
95 RESTORE_INT_REG (ra, 1, t0)
96 RESTORE_INT_REG (sp, 2, t0)
97 RESTORE_INT_REG (s0, 8, t0)
98 RESTORE_INT_REG (s1, 9, t0)
99 RESTORE_INT_REG (a0, 10, t0)
100 RESTORE_INT_REG (a1, 11, t0)
101 RESTORE_INT_REG (a2, 12, t0)
102 RESTORE_INT_REG (a3, 13, t0)
103 RESTORE_INT_REG (a4, 14, t0)
104 RESTORE_INT_REG (a5, 15, t0)
105 RESTORE_INT_REG (a6, 16, t0)
106 RESTORE_INT_REG (a7, 17, t0)
107 RESTORE_INT_REG (s2, 18, t0)
108 RESTORE_INT_REG (s3, 19, t0)
109 RESTORE_INT_REG (s4, 20, t0)
110 RESTORE_INT_REG (s5, 21, t0)
111 RESTORE_INT_REG (s6, 22, t0)
112 RESTORE_INT_REG (s7, 23, t0)
113 RESTORE_INT_REG (s8, 24, t0)
114 RESTORE_INT_REG (s9, 25, t0)
115 RESTORE_INT_REG (s10, 26, t0)
116 RESTORE_INT_REG (s11, 27, t0)
117
118 jr t1
119
120
12199: j __syscall_error
122
123PSEUDO_END (__swapcontext)
124
125weak_alias (__swapcontext, swapcontext)
126

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