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Joined 2 years ago
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Cake day: June 11th, 2023

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  • I’m not sure I’d attach any meaning to real names online. There’s a whole group of us whose online names are just things they thought were neat when they were 12. And they’ve just stuck forever. There’s lot of reasons.

    But otherwise, yeah. I’ll spend ten minutes looking up someone’s online profile. Mostly for GitHub if I can find it. If someone’s commenting on public prs and seems nice that’s a big signal.








  • Sorry. I wasn’t clear. If the conditional is constant a compile time you get the dead code optimization. The path not taken is removed. If it’s not constant at you may get the loop invariant movement. But only if the compiler can tell that it’s invariant.

    My point wasn’t that you should always rely on this behavior. At least, I didn’t mean to say that. I suppose what I should have said is more like “in many cases you won’t see any performance difference because the compiler will do that for you anyway.”

    I suppose I have value judgements around that like “generally you should do the thing that is more readable and let the compiler take care of stuff like moving the loop invariant”. That’s been mostly true for me. But only mostly.


  • I don’t believe you have to specify the condition at compile time. I think that optimization would fall under dead code elimination.

    For the invariant code motion stuff the comparison just has to be invariant from start to finish. At least, that’s been my experience. The compiler will just shift the if stement.

    But, like, there are totally times when it can’t figure out that the thing is invariant. And sometimes it’s just more readable to move the if statement out of the loop.