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Re: [PATCH V5, rs6000] Support vrotr<mode>3 for int vector types


On Tue, Aug 06, 2019 at 10:19:34AM +0800, Kewen.Lin wrote:
> on 2019/8/6 上午5:21, Segher Boessenkool wrote:
> > The other case is if not all shift counts are the same.  I'm not sure
> > we actually care much about this case :-)
> 
> Got it, I think even for the "other" case, the neg operation without masking
> is also safe since the hardware instructions do ignore the unrelated bits.

Oh it is perfectly safe.  Only wondering how well we optimise this :-)


Segher


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