ARM ELF
4 ARMAND THUMB-SPECIFIC DEFINITIONS
4.1 ELF header
The following tables summarize the ELF header field values specific to the ARM EABI.
Figure 4-1, ARM-specific machine and ident fields
Field |
Value and meaning |
|
|
|
|
e_ident[EI_CLASS] |
ELFCLASS32—ARM and Thumb processors use 32-bit ELF. |
|
|
|
|
e_ident[EI_DATA] |
ELFDATA2LSB |
when the execution environment is little-endian. |
|
ELFDATA2MSB |
when the execution environment is big-endian. |
|
(see the note immediately below). |
|
|
|
|
e_machine |
EM_ARM (decimal 40). |
|
|
|
|
Note The byte order of all data in an ARM ELF file is the byte order of data in the target execution environment, even if that data will only be consumed in the host (static linker) execution environment. The target byte order may differ from the host byte order.
Figure 4-2, ARM-specific e_flags
Field |
|
Value |
|
Meaning |
|
|
|
|
|
|
|
e_flags |
EF_ARM_HASENTRY |
|
e_entry contains a program-loader entry point (see section |
||
|
|
(0x02) |
|
4.1.1, Entry points, below). |
|
|
|
|
|
|
|
|
EF_ARM_SYMSARESORTED |
|
Each subsection of the symbol table is sorted by symbol value |
||
|
|
(0x04) |
|
(see section 4.4.8, Symbol table order, below) |
|
|
|
|
|
|
|
|
EF_ARM_DYNSYMSUSESEGIDX |
|
Symbols in dynamic symbol tables that are defined in sections |
||
|
|
(0x8) |
|
included in program segment n have st_shndx = n + 1. (see |
|
|
|
|
|
section 4.4.9, Dynamic symbol table entries, below). |
|
|
|
|
|
|
|
|
EF_ARM_MAPSYMSFIRST |
|
Mapping symbols precede other local symbols in the symbol |
||
|
|
(0x10) |
|
table (see section 4.4.8, Symbol table order, below). |
|
|
|
|
|
|
|
|
EF_ARM_EABIMASK |
|
This masks an 8-bit version number, the version of the ARM |
||
|
(0xFF000000) |
|
EABI to which this ELF file conforms. This EABI is version 2. A |
||
|
(current version is 0x02000000) |
|
value of 0 denotes unknown conformance. |
||
|
|
|
|
|
|
Figure 4-3, Interpretation of the entry point |
|
||||
|
|
|
|
||
Field |
|
Value and meaning |
|
||
|
|
|
|||
e_entry |
|
In an executable ELF file, e_entry is the virtual address of the image’s unique entry |
|||
(see section 4.1.1, |
point, or 0 if the image does not have a unique entry point. |
||||
In a re-locatable ELF file, e_entry is the offset of the entry point in the section flagged |
|||||
Entry points, below). |
|||||
|
|
by SHF_ENTRYSECT or 0 if there is no entry point. |
|||
|
|
|
|
|
|
SWS ESPC 0003 B-02 |
Page 27 of 42 |