第六章 語(yǔ)義分析和語(yǔ)法制導(dǎo)翻譯

1、DD 深圳翻譯公司digit.attr=3F.val=3T.val=3digit.attr=5F.val=5T.val=15E.val=15digit.attr=4F.val=4T.val=4E.val=19Print(19)realT T. .t ty yp pe e= =r re ea al lid1L.in=real,id2L.in=real,id3L.in=realD DA A1 12 2- -B B* *6 6+ +產(chǎn)產(chǎn)生生式式語(yǔ)語(yǔ)義義規(guī)規(guī)則則Sid:=EEE1+E2EE1*E2E -E1E (E1)E idE numS.p:= mknode(:=, mkleaf(id, id.en

2、try), E.p)E.p:= mknode(+, E1.p, E2.p)E.p:= mknode(*, E1.p, E2.p)E.p:= mknode(-, 0, E1.p)E.p:= E1.pE.p:= mkleaf(id, id.entry)E.p:=mkleaf(num,num.val):=*-0+*-0id bnum 34id bid cid arootidbidc-01*02idbnum34-05*46+37ida:=98S id := E S.code := E.code | gen( id.place:=E.place ) E E1 + E2 E.place := newtem

3、p; E.code := E1.code | E2.code | gen(E.place:=E1.place+E2.place)E E1 * E2 E.place := newtemp; E.code := E1.code | E2.code | gen(E.place:=E1.place*E2.place) E - E1 E.place := newtemp; E.code := E1.code | gen(E.place:=0-E1.place) E ( E1 ) E.place:= E1.place; E.code:= E1.code E id E.place:= id.place; E

4、.code:= E num E.place:= num.val；E.code:= id:=id111id21num222C.code to to C.true C.true to to C.false = S.nextC.false = S.nextS.beginS.begingoto S.begingoto S.beginS.nextS.nextS.codeS S1 1.code.codeC.trueC.true to S1.next = S.beginS while C do S1 C.code to to C.true C.true to to C.falseC.falseS S1 1.code.codeC.trueC.true to S1.next = S.nextS S2 2.code.codeC.falseC.false to S2.next = S.nextgoto S.nextgoto S.nextS.nextS.nextS.beginS if C then S1 else S2 C.codeC1.cod