DIF_INSTR_RS
mdb_printf("%-4s %%r%u, DIF_VAR(%x)", name, DIF_INSTR_RS(instr), var);
name, type, DIF_INSTR_R2(instr), DIF_INSTR_RS(instr));
name, DIF_INSTR_RS(in), var);
name, type, DIF_INSTR_RS(in));
name, type, DIF_INSTR_R2(in), DIF_INSTR_RS(in));
uint_t rs = DIF_INSTR_RS(instr);