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Re: CONSTANT_POOL_BEFORE_FUNCTION has no effect in tm.h?

Trevor Scroggins <> writes:

> While I still think the choice is arbitrary (why the front and not the
> back--and mine's a lay opinion, I know), what's the generally accepted
> method for reorganizing string literals and other constants to appear
> after the function asm rather than before it? Some targets appear to
> do something similar in TARGET_MACHINE_DEPENDENT_REORG to relocate
> read-only data to a safe jump distance. Where should I begin looking
> in source/documentation to gain an understanding of the process?

I doubt that there is any documentation on this, but I'd be happy to be
surprised.  TARGET_MACHINE_DEPENDENT_REORG is pretty much free to
rearrange things however it likes.

> Also, I don't really grok your example, which probably belies a lack
> of deep understanding of C or GCC or both. In every case I tried,
> 'const int ai[] = { 1 };' (and volatile ...) was translated to an
> immediate value of 1.

If you write

const int ai[] = { 1 };
int main() { }

then in some cases the global const variable will be put into the
readonly section of the object file before the function.


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