Re: Tree inlining for the C front end (part 3 of 3)

[Alexandre Oliva <aoliva at redhat dot com>]

On Sep 25, 2001, Gerald Pfeifer <pfeifer@dbai.tuwien.ac.at> wrote:

> We really, really, really should avoid having a huge regression in
> these respects as we had for the C++ frontend in GCC 3.0 and 3.0.1.

I doubt it would affect C as much as it did C++.  The absence of
implicit inline in C, as is the case for member functions defined
inside a class body in C++, will most definitely make a huge
difference for C.

Anyway, I don't think imposing such requirements on me is fair.  I'm
not introducing the tree inlining infrastructure, I'm just adopting
for C what's already in place for C++.  So, if you're so much
concerned about the problems that were introduced with tree inlining
in C++, you might as well push for disabling tree inlining in C++.  I
find it a far more saner approach to put the change in, and then keep
on working to improve the tree inlining infrastructure and
heuristics.  Not enabling it for C will just let the problem hidden
for longer.

That said, I certainly would appreciate having numbers showing how
much of an improvement (if any) this patch puts in.  I'm not sure I
have access to any commercial benchmarks, though, nor whether I'm
allowed to publish their results, so I may not be able to help here;
I'll look into it.  In any case, I'll get some bootstrap time numbers
for those interested.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me