Runtime statistics

[Martin v. Loewis]

> Does GCC have any facilities to collect runtime information (such as 
> branching statistics) that can be applied to future compilations?  If 
> not, has anyone expressed any interest in adding it?  This is something 
> that could allow us to squeeze a few % more speed from executables.  The 
> best thing to do would be to make this part of the debug/symbol
> information, so that it can be stripped from final compiles (once the
> info has been used).  We don't want .exe's being larger than they have 
> to be.

Please have a look at the -pg, -fprofile-arcs, -ftest-coverage
options. They modify the generated code, so you'll have to perform the
profiling separately.

Regards,
Martin