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
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
|
/*
* Copyright (c) 2008 Mans Rullgard <mans@mansr.com>
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#ifdef __ELF__
# define ELF
#else
# define ELF #
#endif
#if HAVE_AS_FUNC
# define FUNC
#else
# define FUNC #
#endif
#ifndef __has_feature
# define __has_feature(x) 0
#endif
#if HAVE_AS_ARCH_DIRECTIVE
.arch AS_ARCH_LEVEL
#endif
#if HAVE_AS_ARCHEXT_DOTPROD_DIRECTIVE
#define ENABLE_DOTPROD .arch_extension dotprod
#define DISABLE_DOTPROD .arch_extension nodotprod
#else
#define ENABLE_DOTPROD
#define DISABLE_DOTPROD
#endif
#if HAVE_AS_ARCHEXT_I8MM_DIRECTIVE
#define ENABLE_I8MM .arch_extension i8mm
#define DISABLE_I8MM .arch_extension noi8mm
#else
#define ENABLE_I8MM
#define DISABLE_I8MM
#endif
#if HAVE_AS_ARCHEXT_SVE_DIRECTIVE
#define ENABLE_SVE .arch_extension sve
#define DISABLE_SVE .arch_extension nosve
#else
#define ENABLE_SVE
#define DISABLE_SVE
#endif
#if HAVE_AS_ARCHEXT_SVE2_DIRECTIVE
#define ENABLE_SVE2 .arch_extension sve2
#define DISABLE_SVE2 .arch_extension nosve2
#else
#define ENABLE_SVE2
#define DISABLE_SVE2
#endif
DISABLE_DOTPROD
DISABLE_I8MM
DISABLE_SVE
DISABLE_SVE2
/* Support macros for
* - Armv8.3-A Pointer Authentication and
* - Armv8.5-A Branch Target Identification
* features which require emitting a .note.gnu.property section with the
* appropriate architecture-dependent feature bits set.
*
* |AARCH64_SIGN_LINK_REGISTER| and |AARCH64_VALIDATE_LINK_REGISTER| expand to
* PACIxSP and AUTIxSP, respectively. |AARCH64_SIGN_LINK_REGISTER| should be
* used immediately before saving the LR register (x30) to the stack.
* |AARCH64_VALIDATE_LINK_REGISTER| should be used immediately after restoring
* it. Note |AARCH64_SIGN_LINK_REGISTER|'s modifications to LR must be undone
* with |AARCH64_VALIDATE_LINK_REGISTER| before RET. The SP register must also
* have the same value at the two points. For example:
*
* .global f
* f:
* AARCH64_SIGN_LINK_REGISTER
* stp x29, x30, [sp, #-96]!
* mov x29, sp
* ...
* ldp x29, x30, [sp], #96
* AARCH64_VALIDATE_LINK_REGISTER
* ret
*
* |AARCH64_VALID_CALL_TARGET| expands to BTI 'c'. Either it, or
* |AARCH64_SIGN_LINK_REGISTER|, must be used at every point that may be an
* indirect call target. In particular, all symbols exported from a file must
* begin with one of these macros. For example, a leaf function that does not
* save LR can instead use |AARCH64_VALID_CALL_TARGET|:
*
* .globl return_zero
* return_zero:
* AARCH64_VALID_CALL_TARGET
* mov x0, #0
* ret
*
* A non-leaf function which does not immediately save LR may need both macros
* because |AARCH64_SIGN_LINK_REGISTER| appears late. For example, the function
* may jump to an alternate implementation before setting up the stack:
*
* .globl with_early_jump
* with_early_jump:
* AARCH64_VALID_CALL_TARGET
* cmp x0, #128
* b.lt .Lwith_early_jump_128
* AARCH64_SIGN_LINK_REGISTER
* stp x29, x30, [sp, #-96]!
* mov x29, sp
* ...
* ldp x29, x30, [sp], #96
* AARCH64_VALIDATE_LINK_REGISTER
* ret
*
* .Lwith_early_jump_128:
* ...
* ret
*
* These annotations are only required with indirect calls. Private symbols that
* are only the target of direct calls do not require annotations. Also note
* that |AARCH64_VALID_CALL_TARGET| is only valid for indirect calls (BLR), not
* indirect jumps (BR). Indirect jumps in assembly are supported through
* |AARCH64_VALID_JUMP_TARGET|. Landing Pads which shall serve for jumps and
* calls can be created using |AARCH64_VALID_JUMP_CALL_TARGET|.
*
* Although not necessary, it is safe to use these macros in 32-bit ARM
* assembly. This may be used to simplify dual 32-bit and 64-bit files.
*
* References:
* - "ELF for the Arm® 64-bit Architecture"
* https: *github.com/ARM-software/abi-aa/blob/master/aaelf64/aaelf64.rst
* - "Providing protection for complex software"
* https://developer.arm.com/architectures/learn-the-architecture/providing-protection-for-complex-software
*/
#if defined(__ARM_FEATURE_BTI_DEFAULT) && (__ARM_FEATURE_BTI_DEFAULT == 1)
# define GNU_PROPERTY_AARCH64_BTI (1 << 0) // Has BTI
# define AARCH64_VALID_CALL_TARGET hint #34 // BTI 'c'
# define AARCH64_VALID_JUMP_TARGET hint #38 // BTI 'j'
#else
# define GNU_PROPERTY_AARCH64_BTI 0 // No BTI
# define AARCH64_VALID_CALL_TARGET
# define AARCH64_VALID_JUMP_TARGET
#endif
#if defined(__ARM_FEATURE_PAC_DEFAULT)
# if ((__ARM_FEATURE_PAC_DEFAULT & (1 << 0)) != 0) // authentication using key A
# define AARCH64_SIGN_LINK_REGISTER paciasp
# define AARCH64_VALIDATE_LINK_REGISTER autiasp
# elif ((__ARM_FEATURE_PAC_DEFAULT & (1 << 1)) != 0) // authentication using key B
# define AARCH64_SIGN_LINK_REGISTER pacibsp
# define AARCH64_VALIDATE_LINK_REGISTER autibsp
# else
# error Pointer authentication defines no valid key!
# endif
# if ((__ARM_FEATURE_PAC_DEFAULT & (1 << 2)) != 0)
# error Authentication of leaf functions is enabled but not supported in FFmpeg!
# endif
# define GNU_PROPERTY_AARCH64_PAC (1 << 1)
#else
# define GNU_PROPERTY_AARCH64_PAC 0
# define AARCH64_SIGN_LINK_REGISTER
# define AARCH64_VALIDATE_LINK_REGISTER
#endif
#if (GNU_PROPERTY_AARCH64_BTI != 0 || GNU_PROPERTY_AARCH64_PAC != 0) && defined(__ELF__)
.pushsection .note.gnu.property, "a"
.balign 8
.long 4
.long 0x10
.long 0x5
.asciz "GNU"
.long 0xc0000000 /* GNU_PROPERTY_AARCH64_FEATURE_1_AND */
.long 4
.long (GNU_PROPERTY_AARCH64_BTI | GNU_PROPERTY_AARCH64_PAC)
.long 0
.popsection
#endif
.macro function name, export=0, align=2
.macro endfunc
ELF .size \name, . - \name
FUNC .endfunc
.purgem endfunc
.endm
.text
.align \align
.if \export
.global EXTERN_ASM\name
ELF .type EXTERN_ASM\name, %function
FUNC .func EXTERN_ASM\name
EXTERN_ASM\name:
AARCH64_VALID_CALL_TARGET
.else
ELF .type \name, %function
FUNC .func \name
\name:
.endif
.endm
.macro const name, align=2, relocate=0
.macro endconst
ELF .size \name, . - \name
.purgem endconst
.endm
#if HAVE_SECTION_DATA_REL_RO
.if \relocate
.section .data.rel.ro
.else
.section .rodata
.endif
#elif defined(_WIN32)
.section .rdata
#elif !defined(__MACH__)
.section .rodata
#else
.const_data
#endif
.align \align
\name:
.endm
.macro movrel rd, val, offset=0
#if CONFIG_PIC && defined(__APPLE__)
.if \offset < 0
adrp \rd, \val@PAGE
add \rd, \rd, \val@PAGEOFF
sub \rd, \rd, -(\offset)
.else
adrp \rd, \val+(\offset)@PAGE
add \rd, \rd, \val+(\offset)@PAGEOFF
.endif
#elif CONFIG_PIC && defined(_WIN32)
.if \offset < 0
adrp \rd, \val
add \rd, \rd, :lo12:\val
sub \rd, \rd, -(\offset)
.else
adrp \rd, \val+(\offset)
add \rd, \rd, :lo12:\val+(\offset)
.endif
#elif CONFIG_PIC
# if __has_feature(hwaddress_sanitizer)
adrp \rd, :pg_hi21_nc:\val+(\offset)
# else
adrp \rd, \val+(\offset)
# endif
add \rd, \rd, :lo12:\val+(\offset)
#else
ldr \rd, =\val+\offset
#endif
.endm
#define GLUE(a, b) a ## b
#define JOIN(a, b) GLUE(a, b)
#define X(s) JOIN(EXTERN_ASM, s)
#define x18 do_not_use_x18
#define w18 do_not_use_w18
|
