Re: [tree-ssa]: out-of-ssa breaks if something adds a pred

[Daniel Berlin <dberlin at dberlin dot org>]

On Friday, June 6, 2003, at 04:18  PM, Chris Lattner wrote:

> > > IMO, this is a failure of the edge insertion routines or the caller 
> > > of
> > > the
> > > routine.
> >
> > Well, the caller can't know what the inserter did, and what to do to
> > the possibly affected phi's.
>
> OTOH, the inserter cannot possibly know how to update the PHI nodes, 
> only
> the caller can.  If the caller doesn't know how to update the PHI 
> nodes,
> something is seriously wrong.

The inserter created the new bb and edges, it thus should know how to 
update the phi nodes.

> > Plus, the current way we create phi nodes would mean that we'd have to
> > rebuild all the phi's (their number of arguments is fixed at creation
> > time). Diego, what to do here?
>
> Why?  What are you trying to do that requires adding predecessors like
> this?

Committing an edge insertion that ends up adding a new bb.