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version 2011-09-19

CMPS : CoMPare Signed

Substract the second operand (snd register) from the first operand (either si4 or imm16). Change the borrow bit of the result : set if a signed borrow occured, clear otherwise.

Internally, this works just like the SUB instruction but the result is never written. The CMPU instruction is identical but performs an unsigned comparison.