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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D82090

--- Comment #7 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
(In reply to Jeffrey A. Law from comment #6)

> The other is to introduce the solver into the predicate analysis pass whi=
ch
> starts to touch on other ideas I've had.  Namely that thread discovery and
> predicate analysis are closely related.  ie, we could be using predicate
> analysis to discover more threading opportunities and we could be using t=
he
> path solver to prune out infeasible paths for the uninit (and other) pass=
es
> by integrating path solving into predicate analysis.  What you've done is
> the first step in this direction.

It looks like compute_control_dep_chain builds a vectors of edges indicating
paths from DEF to USE.  We may be able to feed a variant of this to the path
solver to determine if the path is reachable.  That is, without having to
search for the path :).

Hmm, there may be something here.=