1.语法文法G[E]如下所示:
–E→E+T | E-T | T
–T→T* F | T/F | F
–F→P^ F | P
–P→(E) | i
E→E+T {E.place:=newtemp; emit(E.place, ‘:=‘, E.place ‘+ ‘, T.place)}
E→E-T {E.place:=newtemp; emit(E.place, ‘:=‘, E.place ‘- ‘, T.place)}
E→T {E.place:=newtemp; emit(E.place, ‘:=‘, T.place)}
T→T* F {T.place:=newtemp; emit(T.place, ‘:=‘, T.place ‘* ‘, F.place)}
T→T/ F {T.place:=newtemp; emit(T.place, ‘:=‘, T.place ‘/ ‘, F.place)}
T→F {T.place:=newtemp; emit(T.place, ‘:=‘, F.place)}
F→P^ F {F.place:=newtemp; emit(F.place, ‘:=‘, P.place ‘^ ‘, F.place)}
F→P {F.place:=newtemp; emit(F.place, ‘:=‘, P.place)}
P→(E) {P.place:=E.place;}
P→i {if i<>nil then emit(P.place, ‘:=‘, i.place) else error}
2.(选做)实验三:语法制导的语义翻译程序
要求:
如
输入:a+b*c,则输出
(*,b,c,T1)
(+,a,T1,T2)
输入:b*(c+b)*d,则输出
(+,c,b,T1)
(*,b,T1,T2)
(*,T2,d,T3)
原文:https://www.cnblogs.com/tao614/p/12053546.html