assembly - Dummy operations handling of Intel processor -

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Of course, I have a little silly question, actually, I'm thinking that some special methods provided by Intel processors Dummy series, i.e., are to execute the NOP instructions efficiently? For example, I can imagine that any pre-fetching system that recognizes NOPs disables them and tries to get some useful instructions. Or is it usually sent to the execution unit according to the general instructions, which means that I can process approximately 5 naps of each cycle (approximately 5 execution units)

thanks, Reinhard <

Discarding them would be a very bad idea: they are often used for busy-waiting if you are < Code> NOP s, you can see your wait-loop very much Create and initiate potential communication overhead.

If you think that NOP s is disabled, you can try HLT which saves some energy or you have a CPU in sleep condition Could also send. However, it only makes sense if you want to "do nothing" for a sufficient time and they usually need a supervisor privilege.


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