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Re: My plans on EH infrastructure
On Wed, Apr 8, 2009 at 5:19 PM, Richard Guenther <rguenther@suse.de> wrote:
>> ? - We ought to be able to prove finitarity of simple loops so we can
>> ? ? DCE more early and won't rely on full loop unrolling to get rid of
>> ? ? empty loops originally initializing dead arrays.
>
> I wonder if CD-DCE should not catch this, but I see that for
>
> ?for(i=0;i<4;++i)
> ? ;
>
> we do
>
> Marking useful stmt: if (i_1 <= 3)
>
> which is already a problem if we want to DCE the loop. ?Can we
> mark the controlling predicate necessary somehow only if we
> mark a stmt necessary in the BBs it controls?
This is just what CD-DCE is supposed to do. If it doesn't work, then
CD-DCE is broken.
Ciao!
Steven