Currently, the TDF_foo flags serve 3 purposes:
1) what kind of dump
2) how detailed to print it
3) auxiliary message control

This addresses #1, which currently uses a bit mask of 
TDF_{TREE,RTL,IPA}, of which exactly one must be set.  The patch changes 
things so that these are now an index value (I hesitate to say 
enumeration, because they're still raw ints).  A TDF_KIND(X) accessor 
extracts this value.  (I left the spare bit between the TDF_KIND_MASK 
and TDF_ADDRESS for the moment.)

In addition I added 'TDF_LANG' for language-specific dump control, of 
which -fdump-translation-unit and -fdump-class-hierarchy become.  And 
can also be controlled by -fdump-lang-all. (rather than -fdump-tree-all)

Next move will be to move -fdump-class-hierarchy into a more generic 
structure (and -fdump-translation-unit, if my patch to remove it is not 
accepted).

ok?

nathan
-- 
Nathan Sidwell