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Reply to @nytpu@tilde.zone
Sun Microdevil Pte Ltd@koakuma@uwu.social (2026-10-15 14:16:05)
@nytpu Itanium has a quite nice two-part set of hints I think

You have the dynamicity hint (sp/dp), where sp (static prediction) makes it so that the processor will never use the dynamic prediction machinery for that branch

And the usual direction ones (tk/nt) (TaKen/Not Taken)

You can combine it like "sptk", "dpnt", etc.
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Sun Microdevil Pte Ltd@koakuma@uwu.social (2026-10-15 14:26:10)
@nytpu I particularly like the sp* ones cus it allows you to put hints on like asserts or errors or exceptions (especially with modern languages already statically optimizing on the assumption that failures are rare anyway) and not have the checks pollute precious branch predictor entries

See also: FloatZone memory sanitizer, it implements the checks by abusing FP exceptions and they reported that not having to dynamically predict branches helps with its performance :blobcatpeekaboo: 

https://www.vusec.net/projects/floatzone/