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The brach predictor it's the bane of programmers. It forces to waste effort to write unreadable branchless code.

X86 should support no-branch-predict-if and dont-predict-goto

You've got it the wrong way around. If the branch predictor was 100% accurate, branchless code would have no performance benefit compared to branching code.

> X86 should support no-branch-predict-if

It almost does. You can use __builtin_expect to hint if the branch is predictable - like assertions. Don't annotate conditionals if they're truly unpredictable. The branch predictor will run, but it's not expensive.

You should prefer using the standardized likely/unlikely attributes instead.

Won't that just stall the pipeline on a modern superscalar core and cause even worse performance?

Yes. I don’t think this person (presumed) knows what a branch predictor does.

Select my post, right click, press search, and Google ai will explain to you basic stuff about branchless programming that you should know already.

There are use cases where branch prediction performs better and others where it performs worse. Ask an AI about branchless programming and when it can improve performance. We need both types of CPU instructions to achieve optimal performance.

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