POS_A
| (cast(Instruction, a)<<POS_A) \
| (cast(Instruction, a)<<POS_A) \
#define POS_C (POS_A + SIZE_A)
#define POS_Ax POS_A
#define GETARG_A(i) getarg(i, POS_A, SIZE_A)
#define SETARG_A(i,v) setarg(i, v, POS_A, SIZE_A)