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Message: [QUOTE="BGB, post: 4216623"] actually, as far as performance is concerned, simple computations are faster than a (mispredicted) jump over them often even on plain x86 (including with floating point, albeit with the partial exception of slow/complex operations like "sqrt()" or "sin()", or large/bulky calculations). so, in my experience it is often a little faster just to do math which works over the entire range, rather than having to add conditionals into the mix. granted, it depends some, as many algorithms are expressed better with conditionals, or need them, so it is not usually worthwhile to try to micro-optimize them out. this situation also causes "switch()" when using a jump table to be a surprisingly expensive operation, which can matter somewhat when using a switch with a decent number of cases in a tight loop (for a small number of cases, compilers will often optimize this by using a slightly faster if-else chain internally, due mostly to branch-predictor magic...). also, memory accesses are very fast when in-cache (almost as fast as with plain registers), and IME it means that having values in registers is not necessarily better performance-wise, since often trying to keep values in registers may lead to a larger total number of loads and stores (due to register spills, ...) so often it will make more sense to leave variables on-stack or similar. IME, there has also been little difference performance with between simple and complex memory addresses, as apparently the processor calculates complex memory addresses more or less for free. actually, the above also results in a possible optimization of calculating integer expressions like "x*4+y" using a "lea" instruction. or such... [/QUOTE]

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