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Re: [Patch, i386] Turn on -fschedule-insns and -fsched-pressure by default for x86-64


On Tue, Dec 07, 2010 at 08:04:45PM +0100, Dominique Dhumieres wrote:
> the vectorization still occurs with -fschedule-insns and -fsched-pressure. One possible
> explanation is that with -fschedule-insns and -fsched-pressure the vectorization is done
> on the implicit inner loops of length 3, for a 2/3 speedup, while without them the
> vectorization is done on the inner explicit loop of length 9, for a 5/9 speedup.
> With this ver naive evaluation I get a 6/5 (~20%) slowdown with -fschedule-insns and 

That doesn't make any sense, because scheduling is a RTL pass, while vectorization is
done much earlier on GIMPLE.

	Jakub


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