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Re: [tree-ssa] Patch ping


Hello,

> I get it, Im looking at it upside down :-). Dummy is in fact the last
> block in the loop, and it 'fallsthru' to the entrance block.  all the
> back edges go to dummy so that there is just one edge back to the top of
> the loop.  I was picturing it such that dummy was the loop entrance,
> sorry :-)
> 
> OK, I think I understand whats going on now :-) I was a little confused
> about moving all the labels too, but I think I have a handle on it too
> now.
> 
> Out of curiosity, rather than copying all the incoming edges from BB to
> dummy, moving all the labels, then redirecting the ones you dont want
> back to BB, why not just create dummy and redirect the incoming edges
> from BB to dummy that you want?  It seems a like a little less work and
> might be a bit clearer to read.  I dont think updating the PHI nodes
> would be any different would it? 

Since it is second level of rewriting the rtl version of the function
:-(.  The rtl version uses split_block that makes it natural to do it
this way, and all this stuff was copied from there when Sebastian
created it.  I will probably clean it up sometime later this week, when
I find a time for it.

> Anyway, the patch is fine.

Thanks.  I had to change the patch a bit due to a conflict with change
in phi node structures, I will send an updated version once it passes
testing.

Zdenek


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