Re: plugin hooks

[Basile STARYNKEVITCH <basile@starynkevitch.net>]

Ian Lance Taylor wrote:
> Basile STARYNKEVITCH <basile@starynkevitch.net> writes:
> 
>> * propose a simple patch to add the PLUGIN_REGISTER_PRAGMA event now?
> 
> Do this.

Will do probably tommorow or this evening!
> 
> On the other hand, skimming your list of hooks, I really question the
> need for, e.g., REPLACE_PASS_MANAGER.  I would want to see a real use
> case there before adding such a hook.

 From several face to face discussions with ICI CTuning people (that it 
Grigori Fursin, Albert Cohen, Zbignew Chamski; all 3 are in CC of this 
reply) I understood that GCC ICI is exactly doing that: it has replaced 
GCC pass manager by its own, which invokes all the existing GCC passes 
in some better order (or better number of invocation) and produces 
better generated code (the tuning is done by machine learning 
techniques; they did run their modified GCC a large number of times and 
did build a database of measures.).

I cannot explain more in details what GCC ICI is actually doing. I hope 
my ICI friends will answer here. Perhaps even Zbignew's latest patches 
are related to the answer.

Regards.


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Basile STARYNKEVITCH         http://starynkevitch.net/Basile/
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