From: Xin Long ...
> Hi, David, Sorry, I'm not sure we're worrying about the cpu cost or
> codes style now ?
>
> For cpu cost, I think 0x848(%r13) operation must be better than the
> generated code of if-else.
Nope - the call xxx(%ryyy) is likely to be a data cache miss and a complete
cpu pipeline stall.
The conditional will be a data cache hit and the code (for one branch)
will be prefetched and speculatively executed.
Some very modern cpu might manage to predict indirect jumps, but for
most it is a full pipeline stall.
David
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