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Re: likely/unlikely macro.
Shinpei Kato wrote:
> Thank you for your reply.
>
> So, for example, the expression "if (likely(prev != next))" is same as "if
> ((prev != next) == 1)", isn't it?
More correct would be next:
if (gcc support __builtin_expect) {
we do nothing and likely(prev!=next) => __builtin_expect((prev!=next),1)
then gcc use this information for optimization, this branch of code
would be more otimized then alternatives.
} else {
likely(prev!=next) => (prev != next)
so we don't break compilation and don't do any optimization.
}
> Then, unlikely is opposite of that.
yes
[snip]
Best regards. Ruslan.
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