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Re: How could I get alias set information from data_reference_p
On Thu, Jul 16, 2009 at 10:45, Daniel Berlin<dberlin@dberlin.org> wrote:
> So if i understand you right, it seems all you've done is inverted the
> existing alias/points-to sets.
> IE instead of saying A has B, C, D in it's alias set, you are saying B
> is in the alias set of A, C is in the alias set of A, D is in the
> alias set of A.
>
> Effectively,
>
> A -> {B, C, D}
> B -> {C, D, E}
> becomes
> B -> A
> C -> A, B
> D -> A ,B
> E -> B
>
Yes, this is correct.
> Then you are assigning numbers to the sets that appear on the RHS.
Correct.
> You still end up with bitmaps, and you still have to intersect them
> (or describe containment some other way and do containment queries).
>
> For a large program, this mapping is actually massive and quite
> expensive to compute
In the case of Graphite, the queries are limited to the data
references within a SCoP. Usually a SCoP does not necessarily contain
huge amount of data references. In the future, we may also set
restrictions on the number of data references that we allow in a SCoP.
Sebastian