1 /* Mach-O compact unwind encoding.
2 Copyright (C) 2014-2022 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
21 #ifndef _MACH_O_UNWIND_H
22 #define _MACH_O_UNWIND_H
24 /* Encodings bits for all cpus. */
25 #define MACH_O_UNWIND_IS_NOT_FUNCTION_START 0x80000000
26 #define MACH_O_UNWIND_HAS_LSDA 0x40000000
27 #define MACH_O_UNWIND_PERSONALITY_MASK 0x30000000
28 #define MACH_O_UNWIND_PERSONALITY_SHIFT 28
30 /* Encodings for x86-64. */
32 /* Kind of encoding (4 bits). */
33 #define MACH_O_UNWIND_X86_64_MODE_MASK 0x0f000000
35 /* Frame is RBP based, using the standard sequence: push %rbp; mov %rsp, %rbp.
36 Non-volatile registers must be saved in the stack starting at %rbp-8 to
37 %rbp-2040 (offset is encoded in offset bits * 8). Registers saved are
38 encoded in registers bits, 3 bits per register. */
39 #define MACH_O_UNWIND_X86_64_MODE_RBP_FRAME 0x01000000
40 #define MACH_O_UNWIND_X86_64_RBP_FRAME_REGISTERS 0x00007FFF
41 #define MACH_O_UNWIND_X86_64_RBP_FRAME_OFFSET 0x00FF0000
43 /* Frameless function, with a small stack size. */
44 #define MACH_O_UNWIND_X86_64_MODE_STACK_IMMD 0x02000000
45 #define MACH_O_UNWIND_X86_64_FRAMELESS_STACK_SIZE 0x00FF0000
46 #define MACH_O_UNWIND_X86_64_FRAMELESS_REG_COUNT 0x00001C00
47 #define MACH_O_UNWIND_X86_64_FRAMELESS_REG_PERMUTATION 0x000003FF
49 /* Frameless function, with a larger stack size. The stack size is the sum
50 of the X in subq $X,%rsp (address of X is at function + stack size bits)
52 #define MACH_O_UNWIND_X86_64_MODE_STACK_IND 0x03000000
53 #define MACH_O_UNWIND_X86_64_FRAMELESS_STACK_ADJUST 0x0000E000
56 #define MACH_O_UNWIND_X86_64_MODE_DWARF 0x04000000
57 #define MACH_O_UNWIND_X86_64_DWARF_SECTION_OFFSET 0x00ffffff
60 #define MACH_O_UNWIND_X86_64_REG_NONE 0
61 #define MACH_O_UNWIND_X86_64_REG_RBX 1
62 #define MACH_O_UNWIND_X86_64_REG_R12 2
63 #define MACH_O_UNWIND_X86_64_REG_R13 3
64 #define MACH_O_UNWIND_X86_64_REG_R14 4
65 #define MACH_O_UNWIND_X86_64_REG_R15 5
66 #define MACH_O_UNWIND_X86_64_REG_RBP 6
68 /* Encodings for x86 (almot the same as x86-64). */
70 /* Kind of encoding (4 bits). */
71 #define MACH_O_UNWIND_X86_MODE_MASK 0x0f000000
73 /* Frame is EBP based, using the standard sequence: push %ebp; mov %esp, %ebp.
74 Non-volatile registers must be saved in the stack starting at %ebp-4 to
75 %ebp-240 (offset is encoded in offset bits * 4). Registers saved are
76 encoded in registers bits, 3 bits per register. */
77 #define MACH_O_UNWIND_X86_MODE_EBP_FRAME 0x01000000
78 #define MACH_O_UNWIND_X86_EBP_FRAME_REGISTERS 0x00007FFF
79 #define MACH_O_UNWIND_X86_EBP_FRAME_OFFSET 0x00FF0000
81 /* Frameless function, with a small stack size. */
82 #define MACH_O_UNWIND_X86_MODE_STACK_IMMD 0x02000000
83 #define MACH_O_UNWIND_X86_FRAMELESS_STACK_SIZE 0x00FF0000
84 #define MACH_O_UNWIND_X86_FRAMELESS_REG_COUNT 0x00001C00
85 #define MACH_O_UNWIND_X86_FRAMELESS_REG_PERMUTATION 0x000003FF
87 /* Frameless function, with a larger stack size. The stack size is the sum
88 of the X in subq $X,%esp (address of X is at function + stack size bits)
90 #define MACH_O_UNWIND_X86_MODE_STACK_IND 0x03000000
91 #define MACH_O_UNWIND_X86_FRAMELESS_STACK_ADJUST 0x0000E000
94 #define MACH_O_UNWIND_X86_MODE_DWARF 0x04000000
95 #define MACH_O_UNWIND_X86_DWARF_SECTION_OFFSET 0x00ffffff
98 #define MACH_O_UNWIND_X86_REG_NONE 0
99 #define MACH_O_UNWIND_X86_REG_EBX 1
100 #define MACH_O_UNWIND_X86_REG_ECX 2
101 #define MACH_O_UNWIND_X86_REG_EDX 3
102 #define MACH_O_UNWIND_X86_REG_EDI 4
103 #define MACH_O_UNWIND_X86_REG_ESI 5
104 #define MACH_O_UNWIND_X86_REG_EBP 6
106 /* Encodings for arm64. */
108 #define MACH_O_UNWIND_ARM64_MODE_MASK 0x0f000000
110 /* Leaf function: FP/LR are *not* saved, none or some non-volatile registers
111 are saved, stack is allocated. The size of the frame (register saved and
112 memory) is encoded in STACK_SIZE in 16 byte units. */
113 #define MACH_O_UNWIND_ARM64_MODE_FRAMELESS 0x02000000
115 #define MACH_O_UNWIND_ARM64_MODE_DWARF 0x03000000
117 /* Standard frame: FP/LR are pushed, SP is copied to FP, then non-volatile
118 registers are saved. */
119 #define MACH_O_UNWIND_ARM64_MODE_FRAME 0x04000000
121 /* Registers (for FRAME). */
122 #define MACH_O_UNWIND_ARM64_FRAME_X19_X20_PAIR 0x00000001
123 #define MACH_O_UNWIND_ARM64_FRAME_X21_X22_PAIR 0x00000002
124 #define MACH_O_UNWIND_ARM64_FRAME_X23_X24_PAIR 0x00000004
125 #define MACH_O_UNWIND_ARM64_FRAME_X25_X26_PAIR 0x00000008
126 #define MACH_O_UNWIND_ARM64_FRAME_X27_X28_PAIR 0x00000010
127 #define MACH_O_UNWIND_ARM64_FRAME_D8_D9_PAIR 0x00000100
128 #define MACH_O_UNWIND_ARM64_FRAME_D10_D11_PAIR 0x00000200
129 #define MACH_O_UNWIND_ARM64_FRAME_D12_D13_PAIR 0x00000400
130 #define MACH_O_UNWIND_ARM64_FRAME_D14_D15_PAIR 0x00000800
132 #define MACH_O_UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK 0x00fff000
133 #define MACH_O_UNWIND_ARM64_DWARF_SECTION_OFFSET 0x00ffffff
135 /* Entry in object file (in __LD,__compact_unwind section). */
137 struct mach_o_compact_unwind_32
139 unsigned char start
[4];
140 unsigned char length
[4];
141 unsigned char encoding
[4];
142 unsigned char personality
[4];
143 unsigned char lsda
[4];
146 struct mach_o_compact_unwind_64
148 unsigned char start
[8];
149 unsigned char length
[4];
150 unsigned char encoding
[4];
151 unsigned char personality
[8];
152 unsigned char lsda
[8];
155 /* Header in images (in __TEXT,__unwind_info). */
157 #define MACH_O_UNWIND_SECTION_VERSION 1 /* Current verion in header. */
158 struct mach_o_unwind_info_header
160 unsigned char version
[4]; /* Currently MACH_O_UNWIND_SECTION_VERSION. */
161 unsigned char encodings_array_offset
[4];
162 unsigned char encodings_array_count
[4];
163 unsigned char personality_array_offset
[4];
164 unsigned char personality_array_count
[4];
165 unsigned char index_offset
[4];
166 unsigned char index_count
[4];
169 These are the encodings shared, for index < encoding_array_count
171 count given by personality_array_count
173 count given by index_count
175 last offset given by lsda offset of last index_entry.
179 struct mach_o_unwind_index_entry
181 unsigned char function_offset
[4];
182 unsigned char second_level_offset
[4];
183 unsigned char lsda_index_offset
[4];
186 struct mach_o_unwind_lsda_index_entry
188 unsigned char function_offset
[4];
189 unsigned char lsda_offset
[4];
192 /* Second level index pages. */
194 #define MACH_O_UNWIND_SECOND_LEVEL_REGULAR 2
195 struct mach_o_unwind_regular_second_level_page_header
197 unsigned char kind
[4];
198 unsigned char entry_page_offset
[2];
199 unsigned char entry_count
[2];
200 /* Array of entries. */
203 struct mach_o_unwind_regular_second_level_entry
205 unsigned char function_offset
[4];
206 unsigned char encoding
[4];
209 #define MACH_O_UNWIND_SECOND_LEVEL_COMPRESSED 3
210 struct mach_o_unwind_compressed_second_level_page_header
212 unsigned char kind
[4];
213 unsigned char entry_page_offset
[2];
214 unsigned char entry_count
[2];
215 unsigned char encodings_offset
[2];
216 unsigned char encodings_count
[2];
217 /* Followed by entries array (one word, see below). */
218 /* Followed by (non-common) encodings array. */
221 /* Compressed entries are one word, containing function offset and encoding
223 #define MACH_O_UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(en) \
225 #define MACH_O_UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX(en) \
226 (((en) >> 24) & 0xFF)
228 #endif /* _MACH_O_UNWIND_H */