profile-guided optimization

[Jan Hubicka]

> Hi,
> 
> I'd like to know how many profile-guided optimizations implemented in GCC.
> I checked the source, and the optimizations such as  "tracer" and "reorder 
> basic block" use the profiling information ( static or real profiling).
> Are there any other optimzations using profiling info?

Yes, many of passes run after the loop optimizer consult profile when
doing various decisions.
For instance if convernsion, register allocation, superblock scheduling,
reg-stack, function reordering and code porducing alignments all use it.

Honza
> 
> 
> thanks.
> 
> Qiong
>