[Cbe-oss-dev] [PATCH 1/3] Fix Unlikely(x) == y

Arjan van de Ven arjan at infradead.org
Tue Feb 19 13:40:27 EST 2008


On Tue, 19 Feb 2008 13:33:53 +1100
Nick Piggin <nickpiggin at yahoo.com.au> wrote:
> 
> Actually one thing I don't like about gcc is that I think it still
> emits cmovs for likely/unlikely branches, which is silly (the gcc
> developers seem to be in love with that instruction). If that goes
> away, then branch hints may be even better.

only for -Os and only if the result is smaller afaik.
(cmov tends to be a performance loss most of the time so for -O2 and such it
isn't used as far as I know.. it does make for nice small code however ;-)

 


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