Control deferred writes?

Oliver Betz list_ob at gmx.net
Fri Dec 3 14:28:55 UTC 2010


Hallo All,

can I tell gcc not to defer writes, possibly only to certain 
variables?

In the coldfire V2 microcontrollers, consecutive register writes are 
slow. Consecutive writes to "off-platform" registers take 12 cycles 
IIRC.

Less a problem if the register writes are not consecutive IOW other 
instructions are executed between the writes.

Therefore it is detrimental to delay writes to these registers if it 
leads to consecutive writes.

After all, it's extremly hard to debug code where everthing is out of 
order. And no, I sometimes can't switch off optimization for 
debugging.

Oliver
-- 
Oliver Betz, Muenchen




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