Re: Salsa20 altivec timings

tomstdenis_at_gmail.com
Date: 09/28/05 

Date: 27 Sep 2005 16:55:27 -0700

xmath wrote:
> It's interesting to note that, due to unavoidable data-dependencies, a
> Salsa20 round must take at least 12 cycles, as absolute CPU-independent
> minimum (unless it offers combined add-rotate, rotate-xor, or xor-add
> instructions that execute in one cycle, something I've never seen in
> any CPU).

ARM offers add-rotate but not the others [it can xor-rotate but not
rotate-xor].

Still not bad cycle counts. Coo!

Tom

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