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Re: [patch] Disable tree-ssa DSE for now


On Tue, 2005-01-18 at 21:58 -0800, Mark Mitchell wrote:
> Daniel Berlin wrote:
> > 
> > 
> > On Tue, 18 Jan 2005, Diego Novillo wrote:
> > 
> >> Steven Bosscher wrote:
> >>
> >>> Thoughts?
> >>>
> >> Well, given your analysis, disabling it is not a bad idea.  OTOH, DSE 
> >> doesn't take a long time to run, does it?  I don't think I've ever 
> >> noticed it.
> >>
> > 
> > Also, just because a pass is fast doesn't mean we should keep it enabled :)
> > Down this path, slowness (because it's unnecessary work) lies.
> > We didn't get slower 30 or 40% a time, it was .7% or .3%
> 
> I agree.  If the optimizer experts agree that this pass is ineffective, 
> Steven's patch should be applied.
It largely depends on what one considers ineffective.  I can say with
absolute confidence that the current implementation is able to eliminate
stores that the RTL implementation is unable to eliminate.




Jeff


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