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Re: [patch] Hookize SMALL_REGISTER_CLASSES
On Wed, May 12, 2010 at 9:09 PM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On 05/12/2010 07:27 PM, Steven Bosscher wrote:
>
>> Way forward would be nice. A nack is also OK. But some feedback, please.
>
> I really don't know. The way that register allocator handles "weird"
> instructions with fixed integer registers is a mystery to me, and the
> delicate balance that is needed to avoid spill failures has been barely
> achieved.
>
> I think that the safest way forward is to disable SMALL_REGISTER_CLASSES
> for 64bit SSE registers, but there we have this xmm0 fixed reg issue
> that makes me a bit nervous.
It's not the worst timing to try even the more aggressive approach. We'll
get bugreports if there are bad side-effects and can revert to the
less aggressive variant (or completely).
Richard.
> Uros.
>