编译原理课程设计报告C语言词法与语法分析器的实现docWord格式.docx
《编译原理课程设计报告C语言词法与语法分析器的实现docWord格式.docx》由会员分享，可在线阅读，更多相关《编译原理课程设计报告C语言词法与语法分析器的实现docWord格式.docx（4页珍藏版）》请在冰豆网上搜索。
}/*判断读取的字符*/staticvoidmatchTokenTypeexpected{iftokenexpected{tokengetToken;
}else{syntaxError“unexpectedtoken-“;
printTokentoken,tokenString;
fprintflisting,““;
}}/*进行语法分析，构建语法树*/TreeNode*declaration_listvoid{TreeNode*tdeclaration;
TreeNode*pt;
whiletokenINT||tokenVOID{TreeNode*qdeclaration;
ifqNULL{iftNULLtpq;
else/*nowpcannotbeNULLeither*/{p-siblingq;
pq;
}}}returnt;
}TreeNode*declarationvoid{TreeNode*tNULL;
switchtoken{caseVOIDcaseINTtnewStmtNodeDecK;
iftokenINTt-typeInteger;
elset-typeVoid;
matchtoken;
switchtoken{caseIDt-attr.namecopyStringtokenString;
t-kind.stmtVarDK;
matchID;
switchtoken{caseLZKHt-kind.stmtVarDK;
t-typeIntArray;
matchLZKH;
matchNUM;
matchRZKH;
matchSEMI;
break;
caseLPARENt-kind.stmtFunDK;
matchLPAREN;
t-child[0]params;
matchRPAREN;
t-child[1]compound_stmt;
defaultmatchSEMI;
break;
}break;
defaultsyntaxError“unexpectedtoken-“;
tokengetToken;
defaultsyntaxError“unexpectedtoken-“;
}/*endcase*/returnt;
}TreeNode*paramsvoid{TreeNode*tNULL;
iftokenVOID{matchtoken;
tnewStmtNodeParamList;
t-child[0]newStmtNodeParamK;
t-child[0]-typeVoid;
}elseiftokenRPARENtNULL;
else{tparam_list;
}returnt;
}TreeNode*param_listvoid{TreeNode*tnewStmtNodeParamList;
inti1;
t-child[0]param;
whiletokenRPAREN{matchDOT;
t-child[i]param;
i;
}TreeNode*paramvoid{TreeNode*tNULL;
matchINT;
tnewStmtNodeParamK;
t-typeInteger;
t-attr.namecopyStringtokenString;
iftokenLZKH{t-typeIntArray;
}TreeNode*compound_stmtvoid{TreeNode*tnewStmtNodeComK;
matchLDKH;
t-child[0]local_declarations;
t-child[1]statement_list;
matchRDKH;
returnt;
}TreeNode*local_declarationsvoid{TreeNode*tnewStmtNodeLocalDecK;
inti0;
whiletokenINT||tokenVOID{t-child[i]declaration;
}TreeNode*statement_listvoid{TreeNode*tnewStmtNodeStmtList;
whiletokenRDKH{t-child[i]statement;
}TreeNode*statementvoid{TreeNode*t;
switchtoken{caseIFtif_stmt;
caseWHILEtwhile_stmt;
caseIDcaseSEMItexpression_stmt;
caseRETURNtreturn_stmt;
caseLDKHtcompound_stmt;
}TreeNode*expression_stmtvoid{TreeNode*tnewStmtNodeExpstmtK;
iftokenSEMImatchSEMI;
else{texpression;
}TreeNode*if_stmtvoid{TreeNode*tnewStmtNodeIfK;
iftNULL{matchIF;
t-child[0]expression;
t-child[1]statement;
iftokenELSE{matchELSE;
iftNULLt-child[2]newStmtNodeElseK;
t-child[2]-child[0]statement;
}}returnt;
}TreeNode*while_stmtvoid{TreeNode*tnewStmtNodeWhileK;
matchWHILE;
iftNULLt-child[0]expression;
iftNULLt-child[1]statement;
}TreeNode*return_stmtvoid{TreeNode*tnewStmtNodeRetK;
iftokenRETURNmatchRETURN;
else{t-child[0]expression;
}TreeNode*expressionvoid{TreeNode*tsimple_exp;
}TreeNode*varvoid{TreeNode*tnewExpNodeIdK;
iftNULLmatchID;
iftokenLZKH{matchtoken;
t-typeArrayUnit;
}TreeNode*simple_expvoid{TreeNode*tadditive_expression;
iftNULL{iftokenLT||tokenLE||tokenMT||tokenME||tokenEQ||tokenNEQ{TreeNode*pnewExpNodeOpK;
ifpNULL{p-attr.optoken;
p-child[0]t;
p-child[1]additive_expression;
tp;
}TreeNode*additive_expressionvoid{TreeNode*tterm;
whiletokenPLUS||tokenMINUS{TreeNode*pnewExpNodeOpK;
p-attr.optoken;
p-child[1]term;
tp;
}TreeNode*termvoid{TreeNode*tfactor;
whiletokenTIMES||tokenOVER{TreeNode*pnewExpNodeOpK;
ifpNULL{p-child[0]t;
p-child[1]factor;
}}returnt;
}TreeNode*factorvoid{TreeNode*tNULL;
switchtoken{caseNUMtnewExpNodeConstK;
iftNULLmatchNUM;
caseIDtvar;
iftokenASSIGN{TreeNode*pnewStmtNodeAssignK;
p-attr.namet-attr.name;
p-child[0]expression;
}iftokenLPAREN{TreeNode*pnewStmtNodeCallK;
p-child[0]args;
caseLPARENmatchLPAREN;
texpression;
}TreeNode*argsvoid{TreeNode*tnewStmtNodeArgList;
iftokenRPAREN{t-child[0]arg_list;
}elsereturnNULL;
}TreeNode*arg_listvoid{TreeNode*tnewStmtNodeArgK;
iftokenRPARENt-child[0]expression;
whiletokenRPAREN{matchDOT;
t-child[i]expression;
}TreeNode*parsevoid{TreeNode*t;
tdeclaration_list;
iftokenENDFILEsyntaxError“Codeendsbeforefile\n“;
}scan.cppinclude“globals.h“include“util.h“include“scan.h“/*对扫描的字符进行匹配判断*/TokenTypegetTokenvoid{/*indexforstoringintotokenString*/inttokenStringIndex0;
/*holdscurrenttokentobereturned*/TokenTypecurrentToken;
/*currentstate-alwaysbeginsatSTART*/StateTypestateSTART;
/*flagtoindicatesavetotokenString*/intsave;
whilestateDONE{intcgetNextChar;
saveTRUE;
switchstate{caseSTARTifisdigitcstateINNUM;
elseifisalphacstateINID;
elseifcstateINEQUAL;
elseifcstateINME;
elseifc||c\t||c\nsaveFALSE;
elseifcstateINNEQ;
elseifc/{ifgetNextChar*{ungetNextChar;
stateDONE;
currentTokenOVER;
}else{saveFALSE;
stateINCOMMENT;
}}else{stateDONE;
switchc{caseEOFsaveFALSE;
currentTokenENDFILE;
casecurrentTokenPLUS;
case-currentTokenMINUS;
case*currentTokenTIMES;
casecurrentTokenLPAREN;
casecurrentTokenRPAREN;
case;
currentTokenSEMI;
case[currentTokenLZKH;
case]currentTokenRZKH;
case{currentTokenLDKH;
case}currentTokenRDKH;
case,currentTokenDOT;
defaultcurrentTokenERROR;
}}break;
caseINCOMMENTsaveFALSE;
ifcEOF{stateDONE;
currentTokenERROR;
}elseifc*{ifgetNextChar/{stateSTART;
}else{ungetNextChar;
caseINNEQstateDONE;
ifccurrentTokenNEQ;
else{ungetNextChar;
saveFALSE;
currentTokenERROR;
caseINEQUALstateDONE;
ifccurrentTokenEQ;
else{/*backupintheinput*/ungetNextChar;
currentTokenASSIGN;
caseINNUMifisdigitc{/*backupintheinput*/ungetNextChar;
saveFALSE;
currentTokenNUM;
caseINIDifisalphac{/*backupintheinput*/ungetNextChar;
currentTokenID;
caseINLEstateDONE;
ifccurrentTokenLE;
currentTokenLT;
caseINMEstateDONE;
ifccurrentTokenME;
currentTokenMT;
caseDONEdefault/*shouldneverhappen*/fprintflisting,“ScannerBugstated\n“,state;
}ifsavebreak;
caseNEQfprintflisting,“\n“;
caseASSIGNfprintflisting,“\n“;
caseDOTfprintflisting,“,\n“;
caseLZKHfprintflisting,“[\n“;
caseRZKHfprintflisting,“]\n“;
caseLDKHfprintflisting,“{\n“;
caseRDKHfprintflisting,“}\n“;
caseLZSfprintflisting,“/*\n“;
caseRZSfprintflisting,“*/\n“;
caseMEfprintflisting,“\n“;
caseLEfprintflisting,“child[i]NULL;
}t-siblingNULL;
t-nodekindStmtK;
t-kind.stmtkind;
t-linenolineno;
}/*FunctionnewExpNodecreatesanewexpressionnodeforsyntaxtreeconstruction*/TreeNode*newExpNodeExpKindkind{TreeNode*tTreeNode*mallocsizeofTreeNode;
inti;
iftNULL{fprintflisting,“Outofmemoryerroratlined\n“,lineno;
}else{fori0;
ichild[i]NULL;
t-nodekindExpK;
t-kind.expkind;
t-typeVoid;
}char*copyStringchar*s{intn;
char*t;
ifsNULL{returnNULL;
}nstrlens1;
tchar*mallocn;
/*其作用是在内存的动态存储区中分配一个长度为n的连续空间.保存tokenstring*/iftNULL{fprintflisting,“Outofmemoryerroratlined\n“,lineno;
}else{strcpyt,s;
/*该函数是字符串拷贝函数，用来将一个字符串复制到一个字符数组中。
*//*例如strcpystr1,“china“；
作用是将”China“这个字符串拷贝到str1数组中*/}returnt;
}staticintindentno0;
defineINDENTindentno2defineUNINDENTindentno-2staticvoidprintSpacesvoid{inti;
fori0;
inodekindStmtK{switchtree-kind.stmt{caseIfKfprintflisting,“If\n“;
caseWhileKfprintflisting,“While\n“;
caseElseKfprintfl
升级会员 