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Re: CONSTANT_POOL_BEFORE_FUNCTION has no effect in tm.h?
Trevor Scroggins <trevor.scroggins@gmail.com> writes:
> What I'd like to do is place all constant and read-only data, which I
> now think means all data affected by CONSTANT_POOL_BEFORE_FUNCTION and
> READONLY_DATA_SECTION_ASM_OP (and others?); however, I'd like local,
> read-only data--strings and whatnot--to stay in .text, stored after
> the function rather than prior to it. More specifically, the data
> should be stored in a location appropriate for the addressing mode, as
> long as that location is not before the first instruction in .text.
> e.g.:
>
> .text
> # NOT HERE
> .even
> .globl _main
> _main:
> ...
> rts
> # HERE
> LC0:
> .ascii "this is a string\0"
> LC1:
> .ascii "this is another string\0"
>
> Will I need to "optimize" the location of the data myself?
Most targets put constant strings and the like in the .rodata section.
Then the linker script can put that in a useful place. That seems like
the best approach to use for a processor like m68k which supports
general addressing. I'm surprised that doesn't happen already. I
assume you are using an ELF target, in which case I would expect
default_elf_select_rtx_section to do the right thing.
Ian