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A comment on RISC-V formal spec public review. Parent comment

Re:RISC-V formal spec public review by fluffything on Friday June 21, 2019 @05:33AM (#20241091)
They can't guess, which is why they all offer `__builtin_expect` to control them (which people often wrap in LIKELY/UNLIKELY macros).
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Re:RISC-V formal spec public review by astrange on Friday June 21, 2019 @07:12AM (#20241455)
Yes, but we need the opposite. There's no way to say a branch has no expected value.
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Re:RISC-V formal spec public review by dooglius on Friday June 21, 2019 @09:43AM (#20242396)
Clang does have __builtin_unpredictable, but last I checked it doesn't actually seem to have an effect.
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