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
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
|
/* Copyright (C) 2003, 2004, 2005, 2009 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <tcb-offsets.h>
#ifndef __ASSEMBLER__
# include <pthreadP.h>
#endif
#if !defined NOT_IN_libc || defined IS_IN_libpthread || defined IS_IN_librt
/* NOTE: We do mark syscalls with unwind annotations, for the benefit of
cancellation; but they're really only accurate at the point of the
syscall. The ARM unwind directives are not rich enough without adding
a custom personality function. */
# undef PSEUDO
# define PSEUDO(name, syscall_name, args) \
.section ".text"; \
PSEUDO_PROLOGUE; \
.type __##syscall_name##_nocancel,%function; \
.globl __##syscall_name##_nocancel; \
__##syscall_name##_nocancel: \
cfi_sections(.debug_frame); \
cfi_startproc; \
DO_CALL (syscall_name, args); \
PSEUDO_RET; \
cfi_endproc; \
.size __##syscall_name##_nocancel,.-__##syscall_name##_nocancel; \
ENTRY (name); \
SINGLE_THREAD_P; \
DOARGS_##args; \
bne .Lpseudo_cancel; \
cfi_remember_state; \
DO_CALL (syscall_name, 0); \
UNDOARGS_##args; \
cmn r0, $4096; \
PSEUDO_RET; \
cfi_restore_state; \
.Lpseudo_cancel: \
.fnstart; \
DOCARGS_##args; /* save syscall args etc. around CENABLE. */ \
CENABLE; \
mov ip, r0; /* put mask in safe place. */ \
UNDOCARGS_##args; /* restore syscall args. */ \
ldr r7, =SYS_ify (syscall_name); \
swi 0x0; /* do the call. */ \
.fnend; /* Past here we can't easily unwind. */ \
mov r7, r0; /* save syscall return value. */ \
mov r0, ip; /* get mask back. */ \
CDISABLE; \
mov r0, r7; /* retrieve return value. */ \
RESTORE_LR_##args; \
UNDOARGS_##args; \
cmn r0, $4096
/* DOARGS pushes four bytes on the stack for five arguments, eight bytes for
six arguments, and nothing for fewer. In order to preserve doubleword
alignment, sometimes we must save an extra register. */
# define RESTART_UNWIND \
.fnend; \
.fnstart; \
.save {r7, lr}
# define DOCARGS_0 \
stmfd sp!, {r7, lr}; \
cfi_adjust_cfa_offset (8); \
cfi_rel_offset (r7, 0); \
cfi_rel_offset (lr, 4); \
.save {r7, lr}
# define UNDOCARGS_0
# define RESTORE_LR_0 \
ldmfd sp!, {r7, lr}; \
cfi_adjust_cfa_offset (-8); \
cfi_restore (r7); \
cfi_restore (lr)
# define DOCARGS_1 \
stmfd sp!, {r0, r1, r7, lr}; \
cfi_adjust_cfa_offset (16); \
cfi_rel_offset (r7, 8); \
cfi_rel_offset (lr, 12); \
.save {r7, lr}; \
.pad #8
# define UNDOCARGS_1 \
ldr r0, [sp], #8; \
cfi_adjust_cfa_offset (-8); \
RESTART_UNWIND
# define RESTORE_LR_1 \
RESTORE_LR_0
# define DOCARGS_2 \
stmfd sp!, {r0, r1, r7, lr}; \
cfi_adjust_cfa_offset (16); \
cfi_rel_offset (r7, 8); \
cfi_rel_offset (lr, 12); \
.save {r7, lr}; \
.pad #8
# define UNDOCARGS_2 \
ldmfd sp!, {r0, r1}; \
cfi_adjust_cfa_offset (-8); \
RESTART_UNWIND
# define RESTORE_LR_2 \
RESTORE_LR_0
# define DOCARGS_3 \
stmfd sp!, {r0, r1, r2, r3, r7, lr}; \
cfi_adjust_cfa_offset (24); \
cfi_rel_offset (r7, 16); \
cfi_rel_offset (lr, 20); \
.save {r7, lr}; \
.pad #16
# define UNDOCARGS_3 \
ldmfd sp!, {r0, r1, r2, r3}; \
cfi_adjust_cfa_offset (-16); \
RESTART_UNWIND
# define RESTORE_LR_3 \
RESTORE_LR_0
# define DOCARGS_4 \
stmfd sp!, {r0, r1, r2, r3, r7, lr}; \
cfi_adjust_cfa_offset (24); \
cfi_rel_offset (r7, 16); \
cfi_rel_offset (lr, 20); \
.save {r7, lr}; \
.pad #16
# define UNDOCARGS_4 \
ldmfd sp!, {r0, r1, r2, r3}; \
cfi_adjust_cfa_offset (-16); \
RESTART_UNWIND
# define RESTORE_LR_4 \
RESTORE_LR_0
/* r4 is only stmfd'ed for correct stack alignment. */
# define DOCARGS_5 \
.save {r4}; \
stmfd sp!, {r0, r1, r2, r3, r4, r7, lr}; \
cfi_adjust_cfa_offset (28); \
cfi_rel_offset (r7, 20); \
cfi_rel_offset (lr, 24); \
.save {r7, lr}; \
.pad #20
# define UNDOCARGS_5 \
ldmfd sp!, {r0, r1, r2, r3}; \
cfi_adjust_cfa_offset (-16); \
.fnend; \
.fnstart; \
.save {r4}; \
.save {r7, lr}; \
.pad #4
# define RESTORE_LR_5 \
ldmfd sp!, {r4, r7, lr}; \
cfi_adjust_cfa_offset (-12); \
/* r4 will be marked as restored later. */ \
cfi_restore (r7); \
cfi_restore (lr)
# define DOCARGS_6 \
.save {r4, r5}; \
stmfd sp!, {r0, r1, r2, r3, r7, lr}; \
cfi_adjust_cfa_offset (24); \
cfi_rel_offset (r7, 16); \
cfi_rel_offset (lr, 20); \
.save {r7, lr}; \
.pad #16
# define UNDOCARGS_6 \
ldmfd sp!, {r0, r1, r2, r3}; \
cfi_adjust_cfa_offset (-16); \
.fnend; \
.fnstart; \
.save {r4, r5}; \
.save {r7, lr}
# define RESTORE_LR_6 \
RESTORE_LR_0
# ifdef IS_IN_libpthread
# define CENABLE bl PLTJMP(__pthread_enable_asynccancel)
# define CDISABLE bl PLTJMP(__pthread_disable_asynccancel)
# define __local_multiple_threads __pthread_multiple_threads
# elif !defined NOT_IN_libc
# define CENABLE bl PLTJMP(__libc_enable_asynccancel)
# define CDISABLE bl PLTJMP(__libc_disable_asynccancel)
# define __local_multiple_threads __libc_multiple_threads
# elif defined IS_IN_librt
# define CENABLE bl PLTJMP(__librt_enable_asynccancel)
# define CDISABLE bl PLTJMP(__librt_disable_asynccancel)
# else
# error Unsupported library
# endif
# if defined IS_IN_libpthread || !defined NOT_IN_libc
# ifndef __ASSEMBLER__
extern int __local_multiple_threads attribute_hidden;
# define SINGLE_THREAD_P __builtin_expect (__local_multiple_threads == 0, 1)
# else
# define SINGLE_THREAD_P \
ldr ip, 1b; \
2: \
ldr ip, [pc, ip]; \
teq ip, #0;
# define PSEUDO_PROLOGUE \
1: .word __local_multiple_threads - 2f - 8;
# endif
# else
/* There is no __local_multiple_threads for librt, so use the TCB. */
# ifndef __ASSEMBLER__
# define SINGLE_THREAD_P \
__builtin_expect (THREAD_GETMEM (THREAD_SELF, \
header.multiple_threads) == 0, 1)
# else
# define PSEUDO_PROLOGUE
# define SINGLE_THREAD_P \
stmfd sp!, {r0, lr}; \
cfi_adjust_cfa_offset (8); \
cfi_rel_offset (lr, 4); \
bl __aeabi_read_tp; \
ldr ip, [r0, #MULTIPLE_THREADS_OFFSET]; \
ldmfd sp!, {r0, lr}; \
cfi_adjust_cfa_offset (-8); \
cfi_restore (lr); \
teq ip, #0
# define SINGLE_THREAD_P_PIC(x) SINGLE_THREAD_P
# endif
# endif
#elif !defined __ASSEMBLER__
/* For rtld, et cetera. */
# define SINGLE_THREAD_P 1
# define NO_CANCELLATION 1
#endif
#ifndef __ASSEMBLER__
# define RTLD_SINGLE_THREAD_P \
__builtin_expect (THREAD_GETMEM (THREAD_SELF, \
header.multiple_threads) == 0, 1)
#endif
|
