MIPS did it too with the MIPS16 extension (https://en.wikipedia.org/wiki/MIPS_architecture#Application-specific_extensions https://en.wikipedia.org/wiki/MIPS_ar

MIPS did it too with the MIPS16 extension (https://en.wikipedia.org/wiki/MIPS_architecture#Application-specific_extensions https://en.wikipedia.org/wiki/MIPS_architecture#Application-...) Makes sense as a hardware designer to be able to pick a power- and space-efficient chip. Mashey also had thoughts about that: https://yarchive.net/comp/mips16.html https://yarchive.net/comp/mips16.html Likewise for atomic operations: https://yarchive.net/comp/ll_sc.html https://yarchive.net/comp/ll_sc.html