Andi Kleen wrote:
> - it doesn't seem to help that much on modern CPUs with good
> branch prediction and big icaches anyways.
Really? I would think that as pipelines get deeper (although that trend
seems to have stopped, thankfully) and Icache-miss penalties get relatively
larger we'd see unlikely() becoming MORE of a benefit, not less. Storing
the used part of a "hot" function in 1 Icacheline instead of 4 seems like
an obvious win.
Personally I've never found unlikely() to be ugly; if anything I think
it serves as a nice little human-readable comment about whats going on
in the control-flow. I guess I'm in the minority on that one, though.
-Mitch
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