code: def CWDE(cpu):
          
          bit = Operators.EXTRACT(cpu.AX, 15, 1)
          cpu.EAX = Operators.SEXTEND(cpu.AX, 16, 32)
          cpu.EDX = Operators.SEXTEND(bit, 1, 32)
docs: Converts word to doubleword.
  
          ::
              DX = sign-extend of AX.
  
          :param cpu: current CPU.