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26 lines
886 B
Plaintext
26 lines
886 B
Plaintext
A few short notes on PIC support.
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. References to the symbol "_GLOBAL_OFFSET_TABLE_" are special. These always
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PC relative to the start of the current instruction. Also, they occur
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in "complex" expressions in function prologs, eg.
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move _GLOBAL_OFFSET_TABLE_ + (. - L1 ), %some_register
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The expression parser can't handle these generically, so the expression
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above is recognised as a special case.
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. Some archs have special PIC assembler syntax to reference static and global
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data. This is handled in targ-cpu.c.
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. Correct relocation_info must be output (eg. fields r_jmptable and r_baserel).
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. Internal labels must be output in the symbol table if they are referred to
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by PIC instructions. The linker must allocate a GOT slot for them.
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. The former meaning of the -k switch ("WORKING_DOT" stuff), has been nuked
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in favour of enabling PIC code recognition.
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-pk
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