Re: [tree-ssa][ GC, Virtual operands, and GCing between passes

[Andrew MacLeod <amacleod at redhat dot com>]

On Mon, 2003-12-15 at 17:04, Richard Henderson wrote:
> On Thu, Dec 11, 2003 at 06:13:00PM -0500, Andrew MacLeod wrote:
> > > - A future compacting collector will not work if you do this.
> > 
> > Why not? Its still just an arbitrary vector of size N...
> 
> Because the objects that you've internal pointers to will move.
> 
> Anyway, yer screwed by a compacting collector anyway, since 
> unless you want to slow down your collector significantly, you
> can't have pointers into the *middle* of objects at all.
> 
> For now the best solution would seem to be "void *defs_p" and
> cast to the proper pointer type when you use it.  If the GC
> marker can't deal with "void *", then it needs to be fixed.
> 
> If we ever implement a compacting collector, we'll have to 
> come up with some other way to represent this.  Possibly we
> could do something with either paths down from the statement,
> or <tree,operand> pairs.

Ive got a new best solution which will allow me to use gc, so I dont
have this problem anymore :-)

Andrew