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Re: [PATCH] Fix PR middle-end/28690, indexed load/store performance + reload bug


On Mon, 11 Dec 2006, Dale Johannesen wrote:

> >	Hmm.  There don't appear to be many options.  This is just how 
> >GCC's current register allocator works.  Another intermediate register 
> >class probably would encounter the same problem.
> >
> >	This patch is okay, but please update the comment above the 
> >predicate explaining why accepting anything for reload_in_progress is 
> >necessary.
> 
> I'm doubtful a target-specific fix is the right idea.  Don't other targets
> have the same problem?

Yes, other targets have similar problems, and they use reload_in_progress
and reload_completed for that reason.  Or better yet, they don't use
predicates which reject hardregs accepted by constraints.  Usually (I'm
not saying all the time, I haven't looked in detail at the rs6000 backend)
that's not necessary as register constraints are all that is needed.


Ciao,
Michael.


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