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Re: [0/4] Modulo scheduling with haifa-sched for C6X
On 10/03/11 20:12, Richard Sandiford wrote:
> But what I'm trying to say is that you're not just doing loop
> unrolling followed by scheduling. You're doing loop unrolling,
> followed by scheduling, followed by an overlapping of the unrolled loop
> iterations. It just felt strange that the overlapping was being done
> without any additional alias analysis.
I wouldn't say this is completely accurate either. If we overlap N
iterations of the loop, then we are analyzing and scheduling N
iterations together, so there isn't really additional overlap besides
the loop kernel we find.
The only assumption is that it does not matter whether you analyze
iterations (X .. X + N - 1) or iterations (Y .. Y + N - 1), since they
are indistinguishable at the RTL level. Hence, any schedule we find for
overlapping N iterations must be valid for all starting points.
Bernd