@Cpu                    Return CPU Information              Predefined equate

    The predefined numeric equate @Cpu returns information about the
    currently selected (i.e. at assembly time) processor. It evaluates to
    a number with the following bits set:

       Bit number          Means
       ──────────          ─────
           0               8086 instructions enabled
           1               80186 instructions enabled
           2               80286 instructions enabled
           3               386 instructions enabled
           4               486 instructions enabled
           5               Pentium instructions enabled
           7               Privileged instructions (≥ 80286) enabled
           8               8087 instructions enabled
           10              80287 instructions enabled
           11              387 instructions enabled

    Several of the above bits may be set. For example, a processor like
    the 80286 supports 8086 instructions as well as 80186 instructions,
    so bits 0, 1 and 2 would be set if the CPU is an 80286. Similarly, if
    a 387 was selected, bits 8, 10, and 11 would be set.


    Example:    macro ipushw imm16
                      if @Cpu and 2     ;; 80186+
                         push imm16
                      else
                         mov  ax,imm16
                         push ax
                      endif
                      endm