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Re: Replace rename_ssa_into_ssa with update_ssa
Hello,
> > Great, that's one of the things I wanted to hear for quite some time.
> > I would be even happier to hear this opinion before I was forced to waste
> > my time by working on the specialized "hand-code" SSA updating
> > (instead of speeding up and improving the generic SSA form updating as
> > I wanted to originally), but even this is a progress :-).
> >
> Well, remember that update_ssa is not magic. It's only a
> relatively mindless search and replace pass. Each user has to
> tell it exactly what names need to be replaced with new names.
obviously, nobody can ask for anything more.
> It can only add new PHI nodes for the old names, it will not add
> PHI nodes needed at the fringes of the region to be updated.
What do you mean by "the fringes of the region to be updated"?
Could you provide some example of this behavior? If it is the case
that it is something nonobvious, it might be a good idea to include
it in comments at update_ssa.
Zdenek