MASK1
#define MASK_NUMERIC (MASK0 | MASK1 | MASK2 | MASK3 | MASK4 | MASK5 | MASK6)
{ LVL1, MASK1, '1', LSEL_RUNLEVEL },
#define MASK0(n,p) (~MASK1(n,p))
#define GET_OPCODE(i) (cast(OpCode, ((i)>>POS_OP) & MASK1(SIZE_OP,0)))
((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
#define getarg(i,pos,size) (cast(int, ((i)>>pos) & MASK1(size,0)))
((cast(Instruction, v)<<pos)&MASK1(size,pos))))