bc reg (SUpdate (Loc i) sc) r = bc reg sc False ++ [ASSIGN (L i) reg]
                                ++ clean r
bc reg (SUpdate (Loc i) sc) r = bc reg sc False ++ [ASSIGN (L i) reg]
                                ++ clean r
bc reg (SUpdate (Loc i) sc) r = bc reg sc False ++ [ASSIGN (L i) reg]
                                ++ clean r