From the CPU's point of view, how does it distinguish an assembly code is an ARM code or a Thumb code?

Is there some signal bit represent the code is ARM or Thumb code, this is just my guess.

Hi,

When I read Thumb-2 instruction manual, it is not clear to me about SDIV availability. Especially I do not understand the last line "are not available in ARM state."

Could you explain it to me?

Thanks,

New functionality introduced with Thumb…