[Gomp-discuss] Somethings to think about ....

[Lars Segerlund]

 Hi again,

  I did read Diego's thesis rather thoroughly this weekend, and I'm 
curious if anybody else have done this ? Also I have looked a bit about 
how to do optimizations for chip synthesis, ( which is where the ssa 
form originates from if I'm not totally wrong :-) ) ... and there was 
some usefull stuff there too.

 I have also been looking at the linux support for MP, and NUMA ( which 
was added lately ), and linux does support affinity and NUMA in the 
latest kernels, however to take maximum advantage of this it would be 
quite resonable to do a native port to linux ( using clone instead of 
any thread library ), and only implement the synchronization element's 
needed by openMP.

 Still the first thing to do is to get openMP running with a threading 
library, and perhaps ( if smp safe ) a semaphore library.

 As for the tasks ahead, I think it's not to hard to use the framework 
in the paper to target the GENERIC tree's ( which is the most resonable 
form to target IMHO ). The algoritms for an rather good implementation 
seem's to all be there, and the nice part is that if we extend the 
pragma handling and add a -fgomp to gcc, we should be able to leave most 
of the regulat stuff in place.

 I do however have a question, I know gcc does support barriers, but to 
what extent and in what context ? As far as I understand it it supports 
barriers which prevents sections of code to be handled together, ( tus 
enforcing separate optimization ). I'm still looking, but does anybody 
know if this is correct ?

 I thought that we might as well start documenting what we want to do 
with gcc, the trees and what we have to modify.

 / regards, Lars Segerlund.