new demangler

[Jim Blandy]

Daniel Jacobowitz <drow@mvista.com> writes:
> When I can figure out a few more points of C++ grammar - it's taken me
> a *(!&#@ month so far and it's barely functional... - I'll have an
> efficient solution for breaking down names into the demangler's trees. 
> This will let us get the information we want much more reliably.

When working on big C++ programs, I think I remember seeing that the
mangled and demangled names take up a *lot* of memory.

If that recollection is correct, it might be cool to have GDB store
the trees instead of the names, and throw a bcache at the nodes in
these demangled name trees, working from the leaves upward, to get
maximum sharing.  I bet that would bring the memory requirements down
to something more closely resembling the actual number of classes,
methods, etc. in the program.

I think the trees would be a lot easier to do certain kinds of
matching on, too.  "Is this a user-defined cast operator?"