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Re: A few little loop.c cleanup patches


Michael Hayes wrote:

> 5. For each loop level (starting with innermost loops).
> 
> 5.1 Perform global lifetime analysis.
> 
> 5.2 Perform loop invariant code motion.
> 
> 5.3 Perform local lifetime analysis if register references moved.
> 
> 5.4 Find induction variables.
> 
> 5.5 Perform loop inversion optimizations.
> 
> 5.6 Perform strength reduction of induction variables.
> 
> 5.7 Perform induction variable elimination.
> 
> 5.8 Perform local lifetime analysis if register references moved.
> 
> 5.9 Perform loop unrolling.

This performs loop unrolling after induction variable magic.  Are you
sure that's the "right" (i.e. most profitable) order ?

[ It is the way it is now, but Jan Hubicka told us a few months ago
  he had a patch to turn this order around ]

-- 
Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290
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