llvm-6502/include/llvm/Support/ELF.h

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//===-- llvm/Support/ELF.h - ELF constants and data structures --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This header contains common, non-processor-specific data structures and
// constants for the ELF file format.
//
// The details of the ELF32 bits in this file are largely based on
// the Tool Interface Standard (TIS) Executable and Linking Format
// (ELF) Specification Version 1.2, May 1995. The ELF64 stuff is not
// standardized, as far as I can tell. It was largely based on information
// I found in OpenBSD header files.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_ELF_H
#define LLVM_SUPPORT_ELF_H
#include "llvm/System/DataTypes.h"
#include <cstring>
namespace llvm {
namespace ELF {
typedef uint32_t Elf32_Addr; // Program address
typedef uint16_t Elf32_Half;
typedef uint32_t Elf32_Off; // File offset
typedef int32_t Elf32_Sword;
typedef uint32_t Elf32_Word;
typedef uint64_t Elf64_Addr;
typedef uint64_t Elf64_Off;
typedef int32_t Elf64_Shalf;
typedef int32_t Elf64_Sword;
typedef uint32_t Elf64_Word;
typedef int64_t Elf64_Sxword;
typedef uint64_t Elf64_Xword;
typedef uint32_t Elf64_Half;
typedef uint16_t Elf64_Quarter;
// Object file magic string.
static const char ElfMagic[] = { 0x7f, 'E', 'L', 'F', '\0' };
struct Elf32_Ehdr {
unsigned char e_ident[16]; // ELF Identification bytes
Elf32_Half e_type; // Type of file (see ET_* below)
Elf32_Half e_machine; // Required architecture for this file (see EM_*)
Elf32_Word e_version; // Must be equal to 1
Elf32_Addr e_entry; // Address to jump to in order to start program
Elf32_Off e_phoff; // Program header table's file offset, in bytes
Elf32_Off e_shoff; // Section header table's file offset, in bytes
Elf32_Word e_flags; // Processor-specific flags
Elf32_Half e_ehsize; // Size of ELF header, in bytes
Elf32_Half e_phentsize; // Size of an entry in the program header table
Elf32_Half e_phnum; // Number of entries in the program header table
Elf32_Half e_shentsize; // Size of an entry in the section header table
Elf32_Half e_shnum; // Number of entries in the section header table
Elf32_Half e_shstrndx; // Sect hdr table index of sect name string table
bool checkMagic () const {
return (memcmp (e_ident, ElfMagic, strlen (ElfMagic))) == 0;
}
unsigned char getFileClass () const { return e_ident[4]; }
unsigned char getDataEncoding () { return e_ident[5]; }
};
// 64-bit ELF header. Fields are the same as for ELF32, but with different
// types (see above).
struct Elf64_Ehdr {
unsigned char e_ident[16];
Elf64_Quarter e_type;
Elf64_Quarter e_machine;
Elf64_Half e_version;
Elf64_Addr e_entry;
Elf64_Off e_phoff;
Elf64_Off e_shoff;
Elf64_Half e_flags;
Elf64_Quarter e_ehsize;
Elf64_Quarter e_phentsize;
Elf64_Quarter e_phnum;
Elf64_Quarter e_shentsize;
Elf64_Quarter e_shnum;
Elf64_Quarter e_shstrndx;
};
// File types
enum {
ET_NONE = 0, // No file type
ET_REL = 1, // Relocatable file
ET_EXEC = 2, // Executable file
ET_DYN = 3, // Shared object file
ET_CORE = 4, // Core file
ET_LOPROC = 0xff00, // Beginning of processor-specific codes
ET_HIPROC = 0xffff // Processor-specific
};
// Machine architectures
enum {
EM_NONE = 0, // No machine
EM_M32 = 1, // AT&T WE 32100
EM_SPARC = 2, // SPARC
EM_386 = 3, // Intel 386
EM_68K = 4, // Motorola 68000
EM_88K = 5, // Motorola 88000
EM_486 = 6, // Intel 486 (deprecated)
EM_860 = 7, // Intel 80860
EM_MIPS = 8, // MIPS R3000
EM_PPC = 20, // PowerPC
EM_ARM = 40, // ARM
EM_ALPHA = 41, // DEC Alpha
EM_SPARCV9 = 43, // SPARC V9
EM_X86_64 = 62 // AMD64
};
// Object file classes.
enum {
ELFCLASS32 = 1, // 32-bit object file
ELFCLASS64 = 2 // 64-bit object file
};
// Object file byte orderings.
enum {
ELFDATA2LSB = 1, // Little-endian object file
ELFDATA2MSB = 2 // Big-endian object file
};
// Section header.
struct Elf32_Shdr {
Elf32_Word sh_name; // Section name (index into string table)
Elf32_Word sh_type; // Section type (SHT_*)
Elf32_Word sh_flags; // Section flags (SHF_*)
Elf32_Addr sh_addr; // Address where section is to be loaded
Elf32_Off sh_offset; // File offset of section data, in bytes
Elf32_Word sh_size; // Size of section, in bytes
Elf32_Word sh_link; // Section type-specific header table index link
Elf32_Word sh_info; // Section type-specific extra information
Elf32_Word sh_addralign; // Section address alignment
Elf32_Word sh_entsize; // Size of records contained within the section
};
// Section header for ELF64 - same fields as ELF32, different types.
struct Elf64_Shdr {
Elf64_Half sh_name;
Elf64_Half sh_type;
Elf64_Xword sh_flags;
Elf64_Addr sh_addr;
Elf64_Off sh_offset;
Elf64_Xword sh_size;
Elf64_Half sh_link;
Elf64_Half sh_info;
Elf64_Xword sh_addralign;
Elf64_Xword sh_entsize;
};
// Special section indices.
enum {
SHN_UNDEF = 0, // Undefined, missing, irrelevant, or meaningless
SHN_LORESERVE = 0xff00, // Lowest reserved index
SHN_LOPROC = 0xff00, // Lowest processor-specific index
SHN_HIPROC = 0xff1f, // Highest processor-specific index
SHN_ABS = 0xfff1, // Symbol has absolute value; does not need relocation
SHN_COMMON = 0xfff2, // FORTRAN COMMON or C external global variables
SHN_HIRESERVE = 0xffff // Highest reserved index
};
// Section types.
enum {
SHT_NULL = 0, // No associated section (inactive entry).
SHT_PROGBITS = 1, // Program-defined contents.
SHT_SYMTAB = 2, // Symbol table.
SHT_STRTAB = 3, // String table.
SHT_RELA = 4, // Relocation entries; explicit addends.
SHT_HASH = 5, // Symbol hash table.
SHT_DYNAMIC = 6, // Information for dynamic linking.
SHT_NOTE = 7, // Information about the file.
SHT_NOBITS = 8, // Data occupies no space in the file.
SHT_REL = 9, // Relocation entries; no explicit addends.
SHT_SHLIB = 10, // Reserved.
SHT_DYNSYM = 11, // Symbol table.
SHT_LOPROC = 0x70000000, // Lowest processor architecture-specific type.
SHT_HIPROC = 0x7fffffff, // Highest processor architecture-specific type.
SHT_LOUSER = 0x80000000, // Lowest type reserved for applications.
SHT_HIUSER = 0xffffffff // Highest type reserved for applications.
};
// Section flags.
enum {
SHF_WRITE = 0x1, // Section data should be writable during execution.
SHF_ALLOC = 0x2, // Section occupies memory during program execution.
SHF_EXECINSTR = 0x4, // Section contains executable machine instructions.
SHF_MASKPROC = 0xf0000000 // Bits indicating processor-specific flags.
};
// Symbol table entries.
struct Elf32_Sym {
Elf32_Word st_name; // Symbol name (index into string table)
Elf32_Addr st_value; // Value or address associated with the symbol
Elf32_Word st_size; // Size of the symbol
unsigned char st_info; // Symbol's type and binding attributes
unsigned char st_other; // Must be zero; reserved
Elf32_Half st_shndx; // Which section (header table index) it's defined in
// These accessors and mutators correspond to the ELF32_ST_BIND,
// ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification:
unsigned char getBinding () const { return st_info >> 4; }
unsigned char getType () const { return st_info & 0x0f; }
void setBinding (unsigned char b) { setBindingAndType (b, getType ()); }
void setType (unsigned char t) { setBindingAndType (getBinding (), t); }
void setBindingAndType (unsigned char b, unsigned char t) {
st_info = (b << 4) + (t & 0x0f);
}
};
// Symbol bindings.
enum {
STB_LOCAL = 0, // Local symbol, not visible outside obj file containing def
STB_GLOBAL = 1, // Global symbol, visible to all object files being combined
STB_WEAK = 2, // Weak symbol, like global but lower-precedence
STB_LOPROC = 13, // Lowest processor-specific binding type
STB_HIPROC = 15 // Highest processor-specific binding type
};
// Symbol types.
enum {
STT_NOTYPE = 0, // Symbol's type is not specified
STT_OBJECT = 1, // Symbol is a data object (variable, array, etc.)
STT_FUNC = 2, // Symbol is executable code (function, etc.)
STT_SECTION = 3, // Symbol refers to a section
STT_FILE = 4, // Local, absolute symbol that refers to a file
STT_LOPROC = 13, // Lowest processor-specific symbol type
STT_HIPROC = 15 // Highest processor-specific symbol type
};
// Relocation entry, without explicit addend.
struct Elf32_Rel {
Elf32_Addr r_offset; // Location (file byte offset, or program virtual addr)
Elf32_Word r_info; // Symbol table index and type of relocation to apply
// These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE,
// and ELF32_R_INFO macros defined in the ELF specification:
Elf32_Word getSymbol () const { return (r_info >> 8); }
unsigned char getType () const { return (unsigned char) (r_info & 0x0ff); }
void setSymbol (Elf32_Word s) { setSymbolAndType (s, getType ()); }
void setType (unsigned char t) { setSymbolAndType (getSymbol(), t); }
void setSymbolAndType (Elf32_Word s, unsigned char t) {
r_info = (s << 8) + t;
};
};
// Relocation entry with explicit addend.
struct Elf32_Rela {
Elf32_Addr r_offset; // Location (file byte offset, or program virtual addr)
Elf32_Word r_info; // Symbol table index and type of relocation to apply
Elf32_Sword r_addend; // Compute value for relocatable field by adding this
// These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE,
// and ELF32_R_INFO macros defined in the ELF specification:
Elf32_Word getSymbol () const { return (r_info >> 8); }
unsigned char getType () const { return (unsigned char) (r_info & 0x0ff); }
void setSymbol (Elf32_Word s) { setSymbolAndType (s, getType ()); }
void setType (unsigned char t) { setSymbolAndType (getSymbol(), t); }
void setSymbolAndType (Elf32_Word s, unsigned char t) {
r_info = (s << 8) + t;
};
};
// Program header.
struct Elf32_Phdr {
Elf32_Word p_type; // Type of segment
Elf32_Off p_offset; // File offset where segment is located, in bytes
Elf32_Addr p_vaddr; // Virtual address of beginning of segment
Elf32_Addr p_paddr; // Physical address of beginning of segment (OS-specific)
Elf32_Word p_filesz; // Num. of bytes in file image of segment (may be zero)
Elf32_Word p_memsz; // Num. of bytes in mem image of segment (may be zero)
Elf32_Word p_flags; // Segment flags
Elf32_Word p_align; // Segment alignment constraint
};
// Segment types.
enum {
PT_NULL = 0, // Unused segment.
PT_LOAD = 1, // Loadable segment.
PT_DYNAMIC = 2, // Dynamic linking information.
PT_INTERP = 3, // Interpreter pathname.
PT_NOTE = 4, // Auxiliary information.
PT_SHLIB = 5, // Reserved.
PT_PHDR = 6, // The program header table itself.
PT_LOPROC = 0x70000000, // Lowest processor-specific program hdr entry type.
PT_HIPROC = 0x7fffffff // Highest processor-specific program hdr entry type.
};
// Segment flag bits.
enum {
PF_X = 1, // Execute
PF_W = 2, // Write
PF_R = 4, // Read
PF_MASKPROC = 0xf0000000 // Unspecified
};
} // end namespace ELF
} // end namespace llvm
#endif