Re: Loop optimiser upgrade (Was RFC: BB duplication code)

[Jan Hubicka <jh at suse dot cz>]

> Jan Hubicka writes:
> 
>  > > I'd say strip the loop notes.  You don't really lose any information,
>  > > in that correct information can always be obtained from the shape of
>  > > the CFG, via flow_loop_nodes_find.
>  > Agreed - anyway an loop optimizer is still an barrier for my effort.
>  > Until it is converted to use CFG, we can't make flow info survive.
> 
> I agree that the loop notes should be weeded out.  The one useful loop
> note is the VTOP note that indicates if the loop exit code has been
> duplicated.  When this loop exists and we know that the loop body will
Just to note, the case we were speaking about is the tracer and dropping
loop notes in the code duplicates.
This means that it will not affect current loop optimizer, as the BB
duplication is run afterwards
(but if loop optimizer were sane, it should be run before).

Honza