Given appropriate likeliness annotations or profile-guided optimization, it's po... | Hacker News

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Scaevolus on May 6, 2021 | parent | context | favorite | on: Branch predictor: How many “if”s are too many?

Given appropriate likeliness annotations or profile-guided optimization, it's possible for the compiler to _invert_ the conditional and move the log statement to a "cold" section of code outside of the main flow, making it a never-taken branch.

lttlrck on May 6, 2021 [–]

Yes. I guess that's covered by "it's probably ok"... I'm going to play in godbolt now.

Scaevolus on May 6, 2021 | [–]

-O2 turns it into a "jump if nonzero" without any extra annotations: https://www.godbolt.org/z/j9dfrbosv

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