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Re: PRE (sometimes) confuses ivopts/scev?


On Tue, 25 Jan 2005, Daniel Berlin wrote:

> >>>   if (firstinsideloop ^ secondinsideloop)
> >>
> >> This is pretty much what i'm testing now.
> >
> > This helps - though for the particular function there is now
> >
> > Insertions:0
> > New PHIs:0
> > Eliminated:0
> > Constified:0
> >
> > but I didn't expect any obvious redundant computations in the
> > function anyway.
>
> However, this patch causes us to miss the invariant code in ssa-pre-3.c,
> so we need *some* test there that avoids wraparounds while still catching
> invariant code.

I created PR tree-optimization/19624 with my testcase (took a day to
reduce...).

Richard.

--
Richard Guenther <richard dot guenther at uni-tuebingen dot de>
WWW: http://www.tat.physik.uni-tuebingen.de/~rguenth/


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