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Re: [tree-ssa] Patch ping
Hello,
> > > If you only redirect one edge, aren't you going to create PHI nodes with
> > > one argument? I beleive those are illegal.
> >
> > No they are not. In fact quite many of them are created during
> > optimizations (for example due to jump threading, or when some blocks
> > are removed as unreachable). I am working on a cleanup that removes them,
> > but it still has some problems.
>
> As long as they are removed in a timely fashion. It would be preferable
> not to create them in the first place, it ought to be easy enough to
> check if you are going to redirect more than one edge or not.
thinking about it again, we never use the function in this situation.
We use it to split loops with shared headers, and keeping just one edge
pointing to the newly created forwarder block would obviously not be
useful for this. May I consider the patch approved then?
Zdenek