@kenshirriff The first microprocessor I worked with that had a barrel shifter was at my first job at - port the ( 68000) V7 first to 68010 but a few years later to 68EC040. The '40 had the barrel shifter. Man rotations were zippy. Later for I ported RTOS to and chips. PPC bitfield ops were efficiently done with a bunch of rotate with mask instructions - IMO the pinnacle, the kitchen sink of embedded instructions.