1 //===-- llvm/Support/ELF.h - ELF constants and data structures --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header contains common, non-processor-specific data structures and
11 // constants for the ELF file format.
13 // The details of the ELF32 bits in this file are largely based on
14 // the Tool Interface Standard (TIS) Executable and Linking Format
15 // (ELF) Specification Version 1.2, May 1995. The ELF64 stuff is not
16 // standardized, as far as I can tell. It was largely based on information
17 // I found in OpenBSD header files.
19 //===----------------------------------------------------------------------===//
21 #ifndef LLVM_SUPPORT_ELF_H
22 #define LLVM_SUPPORT_ELF_H
24 #include "llvm/System/DataTypes.h"
31 typedef uint32_t Elf32_Addr; // Program address
32 typedef uint16_t Elf32_Half;
33 typedef uint32_t Elf32_Off; // File offset
34 typedef int32_t Elf32_Sword;
35 typedef uint32_t Elf32_Word;
37 typedef uint64_t Elf64_Addr;
38 typedef uint64_t Elf64_Off;
39 typedef int32_t Elf64_Shalf;
40 typedef int32_t Elf64_Sword;
41 typedef uint32_t Elf64_Word;
42 typedef int64_t Elf64_Sxword;
43 typedef uint64_t Elf64_Xword;
44 typedef uint32_t Elf64_Half;
45 typedef uint16_t Elf64_Quarter;
47 // Object file magic string.
48 static const char ElfMagic[] = { 0x7f, 'E', 'L', 'F', '\0' };
51 unsigned char e_ident[16]; // ELF Identification bytes
52 Elf32_Half e_type; // Type of file (see ET_* below)
53 Elf32_Half e_machine; // Required architecture for this file (see EM_*)
54 Elf32_Word e_version; // Must be equal to 1
55 Elf32_Addr e_entry; // Address to jump to in order to start program
56 Elf32_Off e_phoff; // Program header table's file offset, in bytes
57 Elf32_Off e_shoff; // Section header table's file offset, in bytes
58 Elf32_Word e_flags; // Processor-specific flags
59 Elf32_Half e_ehsize; // Size of ELF header, in bytes
60 Elf32_Half e_phentsize; // Size of an entry in the program header table
61 Elf32_Half e_phnum; // Number of entries in the program header table
62 Elf32_Half e_shentsize; // Size of an entry in the section header table
63 Elf32_Half e_shnum; // Number of entries in the section header table
64 Elf32_Half e_shstrndx; // Sect hdr table index of sect name string table
65 bool checkMagic () const {
66 return (memcmp (e_ident, ElfMagic, strlen (ElfMagic))) == 0;
68 unsigned char getFileClass () const { return e_ident[4]; }
69 unsigned char getDataEncoding () { return e_ident[5]; }
72 // 64-bit ELF header. Fields are the same as for ELF32, but with different
75 unsigned char e_ident[16];
77 Elf64_Quarter e_machine;
83 Elf64_Quarter e_ehsize;
84 Elf64_Quarter e_phentsize;
85 Elf64_Quarter e_phnum;
86 Elf64_Quarter e_shentsize;
87 Elf64_Quarter e_shnum;
88 Elf64_Quarter e_shstrndx;
93 ET_NONE = 0, // No file type
94 ET_REL = 1, // Relocatable file
95 ET_EXEC = 2, // Executable file
96 ET_DYN = 3, // Shared object file
97 ET_CORE = 4, // Core file
98 ET_LOPROC = 0xff00, // Beginning of processor-specific codes
99 ET_HIPROC = 0xffff // Processor-specific
108 // Machine architectures
110 EM_NONE = 0, // No machine
111 EM_M32 = 1, // AT&T WE 32100
112 EM_SPARC = 2, // SPARC
113 EM_386 = 3, // Intel 386
114 EM_68K = 4, // Motorola 68000
115 EM_88K = 5, // Motorola 88000
116 EM_486 = 6, // Intel 486 (deprecated)
117 EM_860 = 7, // Intel 80860
118 EM_MIPS = 8, // MIPS R3000
119 EM_PPC = 20, // PowerPC
121 EM_ALPHA = 41, // DEC Alpha
122 EM_SPARCV9 = 43, // SPARC V9
123 EM_X86_64 = 62 // AMD64
126 // Object file classes.
128 ELFCLASS32 = 1, // 32-bit object file
129 ELFCLASS64 = 2 // 64-bit object file
132 // Object file byte orderings.
134 ELFDATA2LSB = 1, // Little-endian object file
135 ELFDATA2MSB = 2 // Big-endian object file
138 // OS ABI identification.
140 ELFOSABI_NONE = 0, // UNIX System V ABI
141 ELFOSABI_HPUX = 1, // HP-UX operating system
142 ELFOSABI_NETBSD = 2, // NetBSD
143 ELFOSABI_LINUX = 3, // GNU/Linux
144 ELFOSABI_HURD = 4, // GNU/Hurd
145 ELFOSABI_SOLARIS = 6, // Solaris
146 ELFOSABI_AIX = 7, // AIX
147 ELFOSABI_IRIX = 8, // IRIX
148 ELFOSABI_FREEBSD = 9, // FreeBSD
149 ELFOSABI_TRU64 = 10, // TRU64 UNIX
150 ELFOSABI_MODESTO = 11, // Novell Modesto
151 ELFOSABI_OPENBSD = 12, // OpenBSD
152 ELFOSABI_OPENVMS = 13, // OpenVMS
153 ELFOSABI_NSK = 14, // Hewlett-Packard Non-Stop Kernel
154 ELFOSABI_AROS = 15, // AROS
155 ELFOSABI_FENIXOS = 16, // FenixOS
156 ELFOSABI_C6000_ELFABI = 64, // Bare-metal TMS320C6000
157 ELFOSABI_C6000_LINUX = 65, // Linux TMS320C6000
158 ELFOSABI_ARM = 97, // ARM
159 ELFOSABI_STANDALONE = 255 // Standalone (embedded) application
162 // X86_64 relocations.
170 R_X86_64_GLOB_DAT = 6,
171 R_X86_64_JUMP_SLOT = 7,
172 R_X86_64_RELATIVE = 8,
173 R_X86_64_GOTPCREL = 9,
180 R_X86_64_DTPMOD64 = 16,
181 R_X86_64_DTPOFF64 = 17,
182 R_X86_64_TPOFF64 = 18,
185 R_X86_64_DTPOFF32 = 21,
186 R_X86_64_GOTTPOFF = 22,
187 R_X86_64_TPOFF32 = 23,
189 R_X86_64_GOTOFF64 = 25,
190 R_X86_64_GOTPC32 = 26,
191 R_X86_64_SIZE32 = 32,
192 R_X86_64_SIZE64 = 33,
193 R_X86_64_GOTPC32_TLSDESC = 34,
194 R_X86_64_TLSDESC_CALL = 35,
195 R_X86_64_TLSDESC = 36
200 Elf32_Word sh_name; // Section name (index into string table)
201 Elf32_Word sh_type; // Section type (SHT_*)
202 Elf32_Word sh_flags; // Section flags (SHF_*)
203 Elf32_Addr sh_addr; // Address where section is to be loaded
204 Elf32_Off sh_offset; // File offset of section data, in bytes
205 Elf32_Word sh_size; // Size of section, in bytes
206 Elf32_Word sh_link; // Section type-specific header table index link
207 Elf32_Word sh_info; // Section type-specific extra information
208 Elf32_Word sh_addralign; // Section address alignment
209 Elf32_Word sh_entsize; // Size of records contained within the section
212 // Section header for ELF64 - same fields as ELF32, different types.
216 Elf64_Xword sh_flags;
222 Elf64_Xword sh_addralign;
223 Elf64_Xword sh_entsize;
226 // Special section indices.
228 SHN_UNDEF = 0, // Undefined, missing, irrelevant, or meaningless
229 SHN_LORESERVE = 0xff00, // Lowest reserved index
230 SHN_LOPROC = 0xff00, // Lowest processor-specific index
231 SHN_HIPROC = 0xff1f, // Highest processor-specific index
232 SHN_ABS = 0xfff1, // Symbol has absolute value; does not need relocation
233 SHN_COMMON = 0xfff2, // FORTRAN COMMON or C external global variables
234 SHN_HIRESERVE = 0xffff // Highest reserved index
239 SHT_NULL = 0, // No associated section (inactive entry).
240 SHT_PROGBITS = 1, // Program-defined contents.
241 SHT_SYMTAB = 2, // Symbol table.
242 SHT_STRTAB = 3, // String table.
243 SHT_RELA = 4, // Relocation entries; explicit addends.
244 SHT_HASH = 5, // Symbol hash table.
245 SHT_DYNAMIC = 6, // Information for dynamic linking.
246 SHT_NOTE = 7, // Information about the file.
247 SHT_NOBITS = 8, // Data occupies no space in the file.
248 SHT_REL = 9, // Relocation entries; no explicit addends.
249 SHT_SHLIB = 10, // Reserved.
250 SHT_DYNSYM = 11, // Symbol table.
251 SHT_LOPROC = 0x70000000, // Lowest processor architecture-specific type.
252 SHT_HIPROC = 0x7fffffff, // Highest processor architecture-specific type.
253 SHT_LOUSER = 0x80000000, // Lowest type reserved for applications.
254 SHT_HIUSER = 0xffffffff // Highest type reserved for applications.
259 SHF_WRITE = 0x1, // Section data should be writable during execution.
260 SHF_ALLOC = 0x2, // Section occupies memory during program execution.
261 SHF_EXECINSTR = 0x4, // Section contains executable machine instructions.
262 SHF_MASKPROC = 0xf0000000 // Bits indicating processor-specific flags.
265 // Symbol table entries.
267 Elf32_Word st_name; // Symbol name (index into string table)
268 Elf32_Addr st_value; // Value or address associated with the symbol
269 Elf32_Word st_size; // Size of the symbol
270 unsigned char st_info; // Symbol's type and binding attributes
271 unsigned char st_other; // Must be zero; reserved
272 Elf32_Half st_shndx; // Which section (header table index) it's defined in
274 // These accessors and mutators correspond to the ELF32_ST_BIND,
275 // ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification:
276 unsigned char getBinding () const { return st_info >> 4; }
277 unsigned char getType () const { return st_info & 0x0f; }
278 void setBinding (unsigned char b) { setBindingAndType (b, getType ()); }
279 void setType (unsigned char t) { setBindingAndType (getBinding (), t); }
280 void setBindingAndType (unsigned char b, unsigned char t) {
281 st_info = (b << 4) + (t & 0x0f);
287 STB_LOCAL = 0, // Local symbol, not visible outside obj file containing def
288 STB_GLOBAL = 1, // Global symbol, visible to all object files being combined
289 STB_WEAK = 2, // Weak symbol, like global but lower-precedence
290 STB_LOPROC = 13, // Lowest processor-specific binding type
291 STB_HIPROC = 15 // Highest processor-specific binding type
296 STT_NOTYPE = 0, // Symbol's type is not specified
297 STT_OBJECT = 1, // Symbol is a data object (variable, array, etc.)
298 STT_FUNC = 2, // Symbol is executable code (function, etc.)
299 STT_SECTION = 3, // Symbol refers to a section
300 STT_FILE = 4, // Local, absolute symbol that refers to a file
301 STT_LOPROC = 13, // Lowest processor-specific symbol type
302 STT_HIPROC = 15 // Highest processor-specific symbol type
305 // Relocation entry, without explicit addend.
307 Elf32_Addr r_offset; // Location (file byte offset, or program virtual addr)
308 Elf32_Word r_info; // Symbol table index and type of relocation to apply
310 // These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE,
311 // and ELF32_R_INFO macros defined in the ELF specification:
312 Elf32_Word getSymbol () const { return (r_info >> 8); }
313 unsigned char getType () const { return (unsigned char) (r_info & 0x0ff); }
314 void setSymbol (Elf32_Word s) { setSymbolAndType (s, getType ()); }
315 void setType (unsigned char t) { setSymbolAndType (getSymbol(), t); }
316 void setSymbolAndType (Elf32_Word s, unsigned char t) {
317 r_info = (s << 8) + t;
321 // Relocation entry with explicit addend.
323 Elf32_Addr r_offset; // Location (file byte offset, or program virtual addr)
324 Elf32_Word r_info; // Symbol table index and type of relocation to apply
325 Elf32_Sword r_addend; // Compute value for relocatable field by adding this
327 // These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE,
328 // and ELF32_R_INFO macros defined in the ELF specification:
329 Elf32_Word getSymbol () const { return (r_info >> 8); }
330 unsigned char getType () const { return (unsigned char) (r_info & 0x0ff); }
331 void setSymbol (Elf32_Word s) { setSymbolAndType (s, getType ()); }
332 void setType (unsigned char t) { setSymbolAndType (getSymbol(), t); }
333 void setSymbolAndType (Elf32_Word s, unsigned char t) {
334 r_info = (s << 8) + t;
338 // Relocation entry, without explicit addend.
340 Elf64_Addr r_offset; // Location (file byte offset, or program virtual addr).
341 Elf64_Xword r_info; // Symbol table index and type of relocation to apply.
343 // These accessors and mutators correspond to the ELF64_R_SYM, ELF64_R_TYPE,
344 // and ELF64_R_INFO macros defined in the ELF specification:
345 Elf64_Xword getSymbol () const { return (r_info >> 32); }
346 unsigned char getType () const {
347 return (unsigned char) (r_info & 0xffffffffL);
349 void setSymbol (Elf32_Word s) { setSymbolAndType (s, getType ()); }
350 void setType (unsigned char t) { setSymbolAndType (getSymbol(), t); }
351 void setSymbolAndType (Elf64_Xword s, unsigned char t) {
352 r_info = (s << 32) + (t&0xffffffffL);
356 // Relocation entry with explicit addend.
358 Elf64_Addr r_offset; // Location (file byte offset, or program virtual addr).
359 Elf64_Xword r_info; // Symbol table index and type of relocation to apply.
360 Elf64_Sxword r_addend; // Compute value for relocatable field by adding this.
362 // These accessors and mutators correspond to the ELF64_R_SYM, ELF64_R_TYPE,
363 // and ELF64_R_INFO macros defined in the ELF specification:
364 Elf64_Xword getSymbol () const { return (r_info >> 32); }
365 unsigned char getType () const {
366 return (unsigned char) (r_info & 0xffffffffL);
368 void setSymbol (Elf64_Xword s) { setSymbolAndType (s, getType ()); }
369 void setType (unsigned char t) { setSymbolAndType (getSymbol(), t); }
370 void setSymbolAndType (Elf64_Xword s, unsigned char t) {
371 r_info = (s << 32) + (t&0xffffffffL);
377 Elf32_Word p_type; // Type of segment
378 Elf32_Off p_offset; // File offset where segment is located, in bytes
379 Elf32_Addr p_vaddr; // Virtual address of beginning of segment
380 Elf32_Addr p_paddr; // Physical address of beginning of segment (OS-specific)
381 Elf32_Word p_filesz; // Num. of bytes in file image of segment (may be zero)
382 Elf32_Word p_memsz; // Num. of bytes in mem image of segment (may be zero)
383 Elf32_Word p_flags; // Segment flags
384 Elf32_Word p_align; // Segment alignment constraint
389 PT_NULL = 0, // Unused segment.
390 PT_LOAD = 1, // Loadable segment.
391 PT_DYNAMIC = 2, // Dynamic linking information.
392 PT_INTERP = 3, // Interpreter pathname.
393 PT_NOTE = 4, // Auxiliary information.
394 PT_SHLIB = 5, // Reserved.
395 PT_PHDR = 6, // The program header table itself.
396 PT_LOPROC = 0x70000000, // Lowest processor-specific program hdr entry type.
397 PT_HIPROC = 0x7fffffff // Highest processor-specific program hdr entry type.
400 // Segment flag bits.
405 PF_MASKPROC = 0xf0000000 // Unspecified
408 } // end namespace ELF
410 } // end namespace llvm