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Re: Using bt,bts


On Wed, Sep 26, 2012 at 10:34 AM, OndÅej BÃlka <neleai@seznam.cz> wrote:

> is there a reason why for example
> x=x|(1<<11);
> is not expanded into
> bts rax,11
> ?

The bts instruction is never faster than the corresponding or
instruction.  There's no reason to use it when setting a bit in the
low 32 bits.

Ian


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