编译原理之语法制导的语义翻译

E→E+T | E-T | T 
T→T* F | T/F | F 
F→P^ F | P 
P→(E) | i 

E→E1+T1   {E.place:=newtemp; emit(E.place , ":=" ,E1.place,‘+‘ , T1.place)} (+, E1.val ,T1.val,E.val)　
E→E1-T1 {E.place:=newtemp; emit(E.place , ":=" ,E1.place,‘-‘ , T1.place)} (-, E1.val ,T1.val,E.val)
E→T1 {E.place:=T1.place;}
T→T1* F1 {T.place:=newtemp; emit(T.place , ":=" ,T1.place,‘*‘ , F1.place)} (*, T1.val ,F1.val,T.val)
T→T1/F1 {T.place:=newtemp; emit(T.place , ":=" , T1.place,‘/‘ , F1.place)}　(/, T1.val ,F1.val,T.val)
T→F1 {T.place:=F1.place;}
F→P1^F1 {T.place:=newtemp; emit(F.place , ":=" , P1.place,‘^‘ , F1.place)}(^, P1.val ,F1.val,F.val)
F→P1  {F.place:=newtemp; emit(F.place , ":=" , P1.place)}
P→(E1)　{P.place:=E1.place}
P→i　{P:=lookup(id.name); if P<>nil then P.place:=i  else error}