On 3 June 2014 01:56, Robin Vowels <[email protected]> wrote:
> XR Rn,Rn is faster than SR. > But does it matter? > Such an instruction should be executed only once, and once only. > It shouldn't be in the loop. > So why is it faster? I suppose "faster" means it would allow more options for it to overlap with previous or following instructions? Not obvious to me. Wouldn't the SR know the condition code upfront as well? I briefly looked at shifting the bytes with SLDA to replace the IC for every byte. But the penalty seemed the need to clear the register before shifting the byte in. An XR or SR or whatever in the loop. I don't see how one could prevent having that in the loop in such a case. Rob
