Doc:Elf:Sections
From GNU 68HC11/HC12
(Difference between revisions)
(Fix indentation) |
|||
| Line 8: | Line 8: | ||
<TR><TD><b>.text</b></TD> | <TR><TD><b>.text</b></TD> | ||
<TD>This is the standard text section for code program. | <TD>This is the standard text section for code program. | ||
| − | + | By default, the linker places the text at 0x8000. This can | |
| − | + | be overridden with <b>-Ttext</b> option. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.rodata</b></TD> | <TR><TD><b>.rodata</b></TD> | ||
<TD>This is the standard read-only data section. It is placed | <TD>This is the standard read-only data section. It is placed | ||
| − | + | after the text section by the linker. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
| Line 23: | Line 23: | ||
<TR><TD><b>.bss</b></TD> | <TR><TD><b>.bss</b></TD> | ||
<TD>This is the standard bss section. It appears after the | <TD>This is the standard bss section. It appears after the | ||
| − | + | data section. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.page0</b></TD> | <TR><TD><b>.page0</b></TD> | ||
<TD>This is a specific section for the 68HC1x to represent the | <TD>This is a specific section for the 68HC1x to represent the | ||
| − | + | page 0. It is intended to be used to help in specifying data | |
| − | + | which are defined in the first 256-bytes (page 0) of the address | |
| − | + | space. It is placed at address 0 by the linker. It is treated as | |
| − | + | a .data section. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.eeprom</b></TD> | <TR><TD><b>.eeprom</b></TD> | ||
<TD>This is a specific section for the 68HC1x to represent the | <TD>This is a specific section for the 68HC1x to represent the | ||
| − | + | internal EEPROM. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.install[0-4]</b></TD> | <TR><TD><b>.install[0-4]</b></TD> | ||
<TD>These sections represent some initialization sections. | <TD>These sections represent some initialization sections. | ||
| − | + | They are used by the GCC startup code. Some of them are for | |
| − | + | used by applications. During the final link, these sections | |
| − | + | are merged with the <b>.text</b> section, and are put at | |
| − | + | beginning. Therefore, they appear at beginning of ROM area. | |
| − | + | The <b>.install0</b> is reserved. It initializes the stack pointer. | |
| − | + | The <b>.install1</b> is a placeholder for applications. | |
| − | + | The <b>.install2</b> is reserved. It initializes the bss and | |
| − | + | data sections. The <b>.install3</b> is a placeholder for applications. | |
| − | + | The <b>.install4</b> is reserved and invokes the main. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.fini[0-4]</b></TD> | <TR><TD><b>.fini[0-4]</b></TD> | ||
| − | + | <TD>These sections represent some termination sections. | |
| − | + | They are used by the GCC finish code (<b>exit</b>). Some of them are for | |
| − | + | used by applications. During the final link, these sections | |
| − | + | are merged with the <b>.text</b> section. <b>.fini0</b> and <b> | |
| − | + | .fini4</b> are reserved. <b>.fini1</b> is a placeholder for | |
| − | + | applications. It can contain code which is executed during exit | |
| − | + | and before the C++ static destructors. <b>.fini2</b> is reserved | |
| − | + | and corresponds to the C++ static destructors. <b>.fini3</b> is | |
| − | + | a placeholder for applications. This code is executed after | |
| − | + | the C++ static destructors are called. The <b>.fini4</b> is | |
| − | + | reserved and corresponds to the runtime exit. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.vectors</b></TD> | <TR><TD><b>.vectors</b></TD> | ||
<TD>This is a specific section for the 68HC1x to represent the | <TD>This is a specific section for the 68HC1x to represent the | ||
| − | + | vectors table. By default the vectors table is located at 0xffc0 | |
| − | + | and placed at that address by the linker. By using the | |
| − | + | <b>-defsym vectors_addr=<i>addr</i></b> linker option, it is | |
| − | + | possible to set another address for the vectors table. For | |
| − | + | example, <b>-defsym vectors_addr=0xbfc0</b> sets the vectors | |
| − | + | table at 0xbfc0. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
<TR><TD><b>.softregs</b></TD> | <TR><TD><b>.softregs</b></TD> | ||
<TD>This is a specific section for the 68HC1x to hold the | <TD>This is a specific section for the 68HC1x to hold the | ||
| − | + | gcc soft registers. For 68HC11, this section is put during the | |
| − | + | final link in the <b>.page0</b> section. For 68HC12, it is | |
| − | + | put in the <b>.bss</b> section. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
| Line 86: | Line 86: | ||
<TR><TD><i>others</i></TD> | <TR><TD><i>others</i></TD> | ||
<TD>Several standard sections exists for DWARF-2 debugging info, | <TD>Several standard sections exists for DWARF-2 debugging info, | ||
| − | + | stack frame unwinding description and so on. | |
</TD> | </TD> | ||
</TR> | </TR> | ||
</TABLE> | </TABLE> | ||
Latest revision as of 23:08, 31 January 2006
ELF sections are defined to organize and classify the data: code, data, readonly data, specific data.
| Section | Description |
| .text | This is the standard text section for code program.
By default, the linker places the text at 0x8000. This can be overridden with -Ttext option. |
| .rodata | This is the standard read-only data section. It is placed
after the text section by the linker. |
| .data | This is the standard data section. |
| .bss | This is the standard bss section. It appears after the
data section. |
| .page0 | This is a specific section for the 68HC1x to represent the
page 0. It is intended to be used to help in specifying data which are defined in the first 256-bytes (page 0) of the address space. It is placed at address 0 by the linker. It is treated as a .data section. |
| .eeprom | This is a specific section for the 68HC1x to represent the
internal EEPROM. |
| .install[0-4] | These sections represent some initialization sections.
They are used by the GCC startup code. Some of them are for used by applications. During the final link, these sections are merged with the .text section, and are put at beginning. Therefore, they appear at beginning of ROM area. The .install0 is reserved. It initializes the stack pointer. The .install1 is a placeholder for applications. The .install2 is reserved. It initializes the bss and data sections. The .install3 is a placeholder for applications. The .install4 is reserved and invokes the main. |
| .fini[0-4] | These sections represent some termination sections.
They are used by the GCC finish code (exit). Some of them are for used by applications. During the final link, these sections are merged with the .text section. .fini0 and .fini4 are reserved. .fini1 is a placeholder for applications. It can contain code which is executed during exit and before the C++ static destructors. .fini2 is reserved and corresponds to the C++ static destructors. .fini3 is a placeholder for applications. This code is executed after the C++ static destructors are called. The .fini4 is reserved and corresponds to the runtime exit. |
| .vectors | This is a specific section for the 68HC1x to represent the
vectors table. By default the vectors table is located at 0xffc0 and placed at that address by the linker. By using the -defsym vectors_addr=addr linker option, it is possible to set another address for the vectors table. For example, -defsym vectors_addr=0xbfc0 sets the vectors table at 0xbfc0. |
| .softregs | This is a specific section for the 68HC1x to hold the
gcc soft registers. For 68HC11, this section is put during the final link in the .page0 section. For 68HC12, it is put in the .bss section. |
| others | Several standard sections exists for DWARF-2 debugging info,
stack frame unwinding description and so on. |
