Messages in this thread | | | Date | Wed, 3 Jan 2007 08:06:29 -0800 (PST) | From | Linus Torvalds <> | Subject | Re: kernel + gcc 4.1 = several problems |
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On Wed, 3 Jan 2007, Alan wrote: > > > cmov is effectively the same cost as a compare and jump, in both cases > > the cpu needs to do a prediction, and on a mispredict, restart. > > On a P4 it appears to be slower than compare/jump in most cases
On just about EVERYTHING it's slower than compare/jump. See my other post on why, together with a (largely untested) test app.
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