[tree-ssa] Death to WFL nodes

[Diego Novillo]

On Tue, 14 Jan 2003, Jeff Law wrote:

> In the new scheme we have a pointer in tree_common which points to
> the file/location information.  We have a single entry cache which
> allows us to share that information across multiple nodes.  The
> single entry cache has a hit rate of roughly 60%.
> 
Perhaps we could avoid this extra pointer in tree_common.  For
the SSA passes, we need to annotate tree nodes with all sorts of
annotations that depend on both the type of tree and its code.
These annotations are stored in the 'ann' field we added in
tree_common.

Right now I'm rewriting the tree annotations to use separate
structure for the different annotations.  We have annotation for
statements, for decls and other expressions.  If we added locus
as another annotation, then it would only need to be created for
the trees that actually need a locus pointer.

In any case, since I'm still not done with this new
implementation, we can leave it for later.

Diego.