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Re: [ping] Re: PATCH: Disable sched1 when optimizing for size


On Sat, 2009-11-21 at 13:32 +0100, Richard Guenther wrote:
> I do not see why scheduling instructions should have an effect on
> code-size.  Appearantly it does for arm, so why not disable scheduling
> from code inside the arm backend instead?
> 

Because it increases max-live which can cause more spilling and a larger
number of registers to save/restore in the prologue/epilogue.

Note, I'm only talking about the pre-regalloc scheduling pass.

As to why do it in the ARM backend only, the answer is obvious -- I
could, but then other ports that would also benefit from this (which is
all of those that do scheduling as far as I can see) would not benefit.

R.




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