http://www.cs.arizona.edu/classes/cs352/spring04/performance-tuning-hints.html
Very good info will help you a lot if you do not know any of this.

Part 1

Heres some info on unrolling a loop for dreamcast.This is a major problem on Gcc most times it does not do this right when using Sh4 side of it. Try this out saves up to 1 to 4 cycles.

Normal

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Please ask permission to copy this tutorial to any site through email or on my forum.
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