I find it odd that the GPRs r12/r13 are used more than r14/r15, because they're both callee-save and the former have more restrictions on their use in memory op

I find it odd that the GPRs r12/r13 are used more than r14/r15, because they're both callee-save and the former have more restrictions on their use in memory operands. Also, the posts mentions video codecs, but if you're doing SW video decoding then you've already failed at performance and power.