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A leap year check in three instructions

(hueffner.de)
420 points gnabgib | 1 comments | 15 May 25 21:57 UTC | HN request time: 1.464s | source
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drewg123 ◴[15 May 25 22:47 UTC] No.44000124[source]▶
I tend to be of the opinion that for modern general purpose CPUs in this era, such micro-optimizations are totally unnecessary because modern CPUs are so fast that instructions are almost free.

But do you know what's not free? Memory accesses[1]. So when I'm optimizing things, I focus on making things more cache friendly.

[1] http://gec.di.uminho.pt/discip/minf/ac0102/1000gap_proc-mem_...

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kreco ◴[15 May 25 23:06 UTC] No.44000255[source]▶
> such micro-optimizations are totally unnecessary because modern CPUs are so fast that instructions are almost free.

I'm amazed by the fact there is always someone who will say that such optimization are totally unnecessary.

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1. recursive ◴[15 May 25 23:45 UTC] No.44000462[source]▶
Some people have significant positions on CPU manufacturers, so there will always be at least a few.