On Thu, 2020-01-09 at 22:29 +0100, michal.lowas-rzechonek@xxxxxxxxxxx wrote: > On 01/09, Stotland, Inga wrote: > > > Please don't use bit shifts for division. > > Why? > > Because it's a different operation, and is less readable. It's a > formula, so use math operators for numbers and bit operators for bits. > > For example, idx_pair <<= 12 is fine, because the *context* is > bit-packing. Noone sane would write this as idx_pair *= 4096. This > reasoning applies the other way as well: don't write foo >> 2 where you > mean foo / 4. Well, shift is a less expensive operation than a division (I believe, some compilers may substitute integer division by 2 with a shift). I don't see any reason not to use >> in this particular case, but I can change if this is not readable... > > > > Also, I think it's clearer to write this as: > > > req_size = num_keys * 3 - num_keys % 2 > > > > No, this is not how I read the spec. We need to pack 2 key indices in 3 octets. > > For example, 4 keys are packed in 6 octets and 5 keys are packed in 8 octets. > > Yes, you're right. Sorry. >
