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Re: [PATCH 3/3] Loop flattening on loop-SSA.


On Mon, Nov 8, 2010 at 10:09, Richard Guenther <rguenther@suse.de> wrote:
> loops with a flattened body you mean? ?What I question is the usefullness
> of flattening a complete nest. ?What I also question is whether
> flattening works for outer loops (well - the default # of blocks to
> flatten seems to be so low that we never do that and I guess you'll
> simply ICE flattening an outer loop if you increase that limit).
>

The patch passed bootstrap with the limit set to flatten all loops
with bodies of 1000 basic blocks or less.  I haven't tried more than a
thousand, but I don't see why this transformation wouldn't work for
arbitrarily complex loop nests.

> Thus, I think you should restrict your self to LI_ONLY_INNERMOST.

That's debatable.

Sebastian


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