Feedback-driven optimization

[Jan Hubicka]

> On Sun, Feb 23, 2003 at 02:04:38AM -0500, Robert Myers wrote:
> > One problem: my instincts tell me I should be working with RTL, not 
> > binary, but gcc doesn't permit routine dump of RTL.
> 
> Nope.  You'll have to make your modifications within gcc itself.

Also there is already support for profile feedback in number of
optimizers.  I am not sure how much more can be done in IA-64 specific
way - probably ifcvt can be made to use it better (there are papers
about profile based hyperblock formation, perhaps it is worthwhile to
implement this) and scheduler - there is already code for trace
schedling but it is not done on IA-64 compilation path as it does
scheduling.  The modification would be trivial.  I would be greatly
interested in results of these.

Honza
> 
> > Another problem:  I don't have an IA-64 and probably don't want one.  
> > What I really want is an emulator that can be completely instrumented.
> 
> There isn't a free ia64 simulator.  To my knowledge, there isn't
> even a closed source simulator that is generally available.
> 
> 
> r~