Re: DW_AT_specification and partial symtabs

[David Carlton <carlton@math.stanford.edu>]

On Thu, 12 Jun 2003 13:26:51 -0400, Elena Zannoni <ezannoni@redhat.com> said:

> I wonder, if we are not reaching the end of the usefulness of the
> psymtabs.  I mean, if we start making the psymtab reader behave like
> the symtab reader, how much faster is that going to be, how much
> smaller, etc. 

Yeah, I'm starting to wonder that, too.  This particular situation is
enough of an edge case that I'm actually tempted not to fix the
psymtab reader until I get bug reports from users complaining about
it, because if I do fix it completely then I'll probably make the
psymtab reader slow, make it duplicate lots and lots of the
functionality of the symtab reader, and do it in such a way as to
cause code duplication that will lead to bugs as the two versions slip
out of sync.  So I'm tempted to let things be for now, and wait until
.debug_pubtypes comes along to save the day.

I guess another possibility would be to merge the symtab reader and
psymtab reader, and have there be some variable 'reading_psyms' or
whatever to control what sort of symbols we're creating, how deeply we
descend into trees, etc.

It would be interesting to find out the following:

1) How much is the savings for building a psymtab vs. building a
   symtab?

2) Where is that savings coming from?

If the savings largely comes from not descending into the bodies of
functions, then the current structure should go: we should just merge
the psymtab and symtab readers, but have some flag floating around
that controls whether or not we descend into bodies of functions.

David Carlton
carlton@math.stanford.edu