1 /* Mach-O compact unwind encoding. 2 Copyright (C) 2014 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 5 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. 10 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. 15 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. */ 20 21 #ifndef _MACH_O_UNWIND_H 22 #define _MACH_O_UNWIND_H 23 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 29 30 /* Encodings for x86-64. */ 31 32 /* Kind of encoding (4 bits). */ 33 #define MACH_O_UNWIND_X86_64_MODE_MASK 0x0f000000 34 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_REGSITERS 0x00007FFF 41 #define MACH_O_UNWIND_X86_64_RBP_FRAME_OFFSET 0x00FF0000 42 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 48 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) 51 and stack adjust. */ 52 #define MACH_O_UNWIND_X86_64_MODE_STACK_IND 0x03000000 53 #define MACH_O_UNWIND_X86_64_FRAMELESS_STACK_ADJUST 0x0000E000 54 55 /* Use dwarf. */ 56 #define MACH_O_UNWIND_X86_64_MODE_DWARF 0x04000000 57 #define MACH_O_UNWIND_X86_64_DWARF_SECTION_OFFSET 0x00ffffff 58 59 /* Registers. */ 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 67 68 /* Encodings for x86 (almot the same as x86-64). */ 69 70 /* Kind of encoding (4 bits). */ 71 #define MACH_O_UNWIND_X86_MODE_MASK 0x0f000000 72 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_REGSITERS 0x00007FFF 79 #define MACH_O_UNWIND_X86_EBP_FRAME_OFFSET 0x00FF0000 80 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 86 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) 89 and stack adjust. */ 90 #define MACH_O_UNWIND_X86_MODE_STACK_IND 0x03000000 91 #define MACH_O_UNWIND_X86_FRAMELESS_STACK_ADJUST 0x0000E000 92 93 /* Use dwarf. */ 94 #define MACH_O_UNWIND_X86_MODE_DWARF 0x04000000 95 #define MACH_O_UNWIND_X86_DWARF_SECTION_OFFSET 0x00ffffff 96 97 /* Registers. */ 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 6 105 106 /* Entry in object file (in __LD,__compact_unwind section). */ 107 108 struct mach_o_compact_unwind_32 109 { 110 unsigned char start[4]; 111 unsigned char length[4]; 112 unsigned char encoding[4]; 113 unsigned char personality[4]; 114 unsigned char lsda[4]; 115 }; 116 117 struct mach_o_compact_unwind_64 118 { 119 unsigned char start[8]; 120 unsigned char length[4]; 121 unsigned char encoding[4]; 122 unsigned char personality[8]; 123 unsigned char lsda[8]; 124 }; 125 126 /* Header in images (in __TEXT,__unwind_info). */ 127 128 #define MACH_O_UNWIND_SECTION_VERSION 1 /* Current verion in header. */ 129 struct mach_o_unwind_info_header 130 { 131 unsigned char version[4]; /* Currently MACH_O_UNWIND_SECTION_VERSION. */ 132 unsigned char encodings_array_offset[4]; 133 unsigned char encodings_array_count[4]; 134 unsigned char personality_array_offset[4]; 135 unsigned char personality_array_count[4]; 136 unsigned char index_offset[4]; 137 unsigned char index_count[4]; 138 /* Followed by: 139 - encodings array 140 These are the encodings shared, for index < encoding_array_count 141 - personality array 142 count given by personality_array_count 143 - index entries 144 count given by index_count 145 - lsda index entries 146 last offset given by lsda offset of last index_entry. 147 */ 148 }; 149 150 struct mach_o_unwind_index_entry 151 { 152 unsigned char function_offset[4]; 153 unsigned char second_level_offset[4]; 154 unsigned char lsda_index_offset[4]; 155 }; 156 157 struct mach_o_unwind_lsda_index_entry 158 { 159 unsigned char function_offset[4]; 160 unsigned char lsda_offset[4]; 161 }; 162 163 /* Second level index pages. */ 164 165 #define MACH_O_UNWIND_SECOND_LEVEL_REGULAR 2 166 struct mach_o_unwind_regular_second_level_page_header 167 { 168 unsigned char kind[4]; 169 unsigned char entry_page_offset[2]; 170 unsigned char entry_count[2]; 171 /* Array of entries. */ 172 }; 173 174 struct mach_o_unwind_regular_second_level_entry 175 { 176 unsigned char function_offset[4]; 177 unsigned char encoding[4]; 178 }; 179 180 #define MACH_O_UNWIND_SECOND_LEVEL_COMPRESSED 3 181 struct mach_o_unwind_compressed_second_level_page_header 182 { 183 unsigned char kind[4]; 184 unsigned char entry_page_offset[2]; 185 unsigned char entry_count[2]; 186 unsigned char encodings_offset[2]; 187 unsigned char encodings_count[2]; 188 /* Followed by entries array (one word, see below). */ 189 /* Followed by (non-common) encodings array. */ 190 }; 191 192 /* Compressed entries are one word, containing function offset and encoding 193 index. */ 194 #define MACH_O_UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(en) \ 195 ((en) & 0x00FFFFFF) 196 #define MACH_O_UNWIND_INFO_COMPRESSED_ENTRY_ENCODING_INDEX(en) \ 197 (((en) >> 24) & 0xFF) 198 199 #endif /* _MACH_O_UNWIND_H */ 200