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Re: [PATCH 3/3] Loop flattening on loop-SSA.
On Mon, Nov 15, 2010 at 11:57 PM, Sebastian Pop <sebpop@gmail.com> wrote:
> On Mon, Nov 15, 2010 at 16:49, Sebastian Pop <sebpop@gmail.com> wrote:
>>> Thus, I think you should restrict your self to LI_ONLY_INNERMOST.
>>
>> That's debatable.
>
> I just happened looking at the definition of
>
> ?LI_ONLY_INNERMOST = 4 ? ? ? ? /* Iterate only over innermost loops. ?*/
>
> It makes no sense to call loop flattening on the innermost loop:
> innermost loops contain zero inner loops, so there is nothing to flatten...
Oh, so you're not removing the loop you are applying to (flattening it to its
superloop) but flattening all subloops in loop.
Well. Then there's indeed no suitable order for you (there's no
LI_FROM_OUTERMOST which would then make sense).
Which means that IMHO it makes sense to only apply flattening
to parents of innermost loops (which is what I tried to suggest).
Any benchmark results yet?
Thanks,
Richard.
> Sebastian
>