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Re: Re : gcc 3.4 > mainline performance regression


Please don't top-post.  It's very confusing.

Mick CORNUT writes:

 > I don't know exactly if I've understood all your previous
 > explanation (excepted the load & store motion part), but we pointed
 > out 2 different problems:
 > 
 > Pb n°1: depending on the optimization level -03, a[0] and a[1] are
 > being loaded and stored on each loop iteration
 > Pb n°2: depending on the optimization level -0s, the max range
 > limit value (1.000.000) is loaded on each loop iteration
 > (previously in gcc 3.4.2, it was loaded once, then the register
 > holding it was decremented by one until null flag detected)
 > 
 > It seems to me that your current remaks only apply to Pb n°1, am I wrong?

That's right.

Andrew.


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