c-.y

一个编译器的例子,基于c语言,在linux下开发 现在了简单的c语言例子

        ;

initializer
        : assignment_expression              {$$=$1;
	                                                       if(strcmp($1->name,"STRING")==0)
							           arraySize=strlen(literals[$1->strIndex])-1;
								else   
							           arraySize++;
						      }
        | '{' initializer_list '}'                   {$$=$2;}
        ;

initializer_list
        : initializer                            {$$=$1;}
        | initializer_list ',' initializer       
                 {$$=addSibling(addNext(newLeaf("initLst"),$1),
                                  addNext(newLeaf("init"),$3));}
        ;

statement
        : labeled_statement                               {$$=$1;}
        | compound_statement                             {$$=$1;}
        | expression_statement                             {$$=$1;}
        | selection_statement                             {$$=$1;}
        | iteration_statement                             {$$=$1;}
        | jump_statement                             {$$=$1;}
        | print_statement                             {$$=$1;}
        ;

labeled_statement
        : ID ':' statement                                                      {$$=addSibling(newLeaf("label"), addNext(newLeaf("stmt"),$3));
	                                                                                 strcpy($$->value, $1);}
        | CASE constant_expression ':' statement                   {$$=addSibling(newLeaf("case"), 
	                                                                                                addSibling(addNext(newLeaf("consExp"),$2), 
										                                    addNext(newLeaf("stmt"),$4)));}
        | DEFAULT ':' statement                                          {$$=addSibling(newLeaf("default"),addNext(newLeaf("stmt"),$3));}
        ;

compound_statement
        : '{' '}'                                    {$$=NULL;}
        | '{' statement_list '}'                  {$$=$2;}
        | '{' declaration_list '}'                             {$$=$2;}
        | '{' declaration_list statement_list '}'             {$$=addSibling(addNext(newLeaf("decLst"), $2), addNext(newLeaf("stmtLst"), $3));}
	//| error  ';'                              {$$=NULL;symRoot=NULL;}
        ;

declaration_list
        : declaration                             {$$=$1;}
        | declaration_list declaration           {$$=addSibling(addNext(newLeaf("decLst"), $1), addNext(newLeaf("dec"), $2));}
        ;

statement_list
        : statement                                                 {$$=$1;}
        | statement_list statement           {$$=addSibling(addNext(newLeaf("stmtLst"), $1),  addNext(newLeaf("stmt"),$2));}
        ;

expression_statement
        : ';'                            {$$=NULL;}
        | expression ';'            {$$=$1;}
        ;

print_statement
        : PRINTLN '(' print_list ')' ';'   {$$=addSibling(newLeaf($1),
                                         addNext(newLeaf("prntLst"),$3));}
	| PRINTLN '(' error ';'    {symRoot=NULL;}
        ;

print_list
        : assignment_expression               {$$=$1;}
        | print_list PRN_OP assignment_expression    
                   {$$=addSibling(addNext(newLeaf("prntLst"),$1),
                                $3);}
        ;  
	
	
selection_statement
        : IF '(' expression ')' statement         
                                  {$$=addSibling(newLeaf("if"),
                                          addSibling(addNext(newLeaf("exp"),$3),
                                                 addNext(newLeaf("stmt"),$5) ));strcpy($$->value,"if");}    
        | IF '(' expression ')' statement ELSE statement
                                 {$$=addSibling(newLeaf("if"),
                                        addSibling(addNext(newLeaf("exp"),$3),
                                                 addSibling(addNext(newLeaf("stmt"),$5),
                                                                   addNext(newLeaf("stmt"),$7))));strcpy($$->value,"ifelse");}
        | SWITCH '(' expression ')' statement        
                                  {$$=addSibling(newLeaf("switch"),
                                          addSibling(addNext(newLeaf("exp"),$3),
                                                 addNext(newLeaf("stmt"),$5) ));}  
        ;

iteration_statement
        : WHILE '(' expression ')' statement
                            {$$=addSibling(newLeaf("while"),
                                    addSibling(addNext(newLeaf("exp"),$3),
                                         addNext(newLeaf("stmt"),$5) ));
				strcpy($$->sibling->value,"while");
				strcpy($$->sibling->sibling->value,"while");
				}
        | DO statement WHILE '(' expression ')' ';'
                             {$$=addSibling(newLeaf("doWhile"),
                                       addSibling(addNext(newLeaf("stmt"),$2),
                                                          addNext(newLeaf("exp"),$5) ));
				strcpy($$->sibling->value,"doWhile");
				strcpy($$->sibling->sibling->value,"doWhile");
				}
        | FOR '(' expression_statement expression_statement ')' statement
                            {   $$=addSibling(newLeaf($1),
                                             addSibling(addNext(newLeaf("expStmt"),$3),
                                                          addSibling(addNext(newLeaf("expStmt"),$4),
                                                                     addNext(newLeaf("stmt"),$6)  )) );
				strcpy($$->sibling->value,"for");
				strcpy($$->sibling->sibling->value,"for");
				strcpy($$->sibling->sibling->sibling->value,"for");}
	                       
        | FOR '(' expression_statement expression_statement expression ')' statement
                              {  $$=addSibling(newLeaf($1),
                                              addSibling(addNext(newLeaf("expStmt"),$3),
                                                           addSibling(addNext(newLeaf("expStmt"),$4),
                                                                     addSibling(addNext(newLeaf("exp"),$5),
                                                                                        addNext(newLeaf("stmt"),$7)  )) ));
				strcpy($$->sibling->value,"for");
				strcpy($$->sibling->sibling->value,"for");
				strcpy($$->sibling->sibling->sibling->value,"for");
				strcpy($$->sibling->sibling->sibling->sibling->value,"for");}
        ;

jump_statement
        : GOTO ID ';'                              {$$=newLeaf("goto");strcpy($$->value, $2);}
        | CONTINUE ';'                           {$$=newLeaf($1);}
        | BREAK ';'                                   {$$=newLeaf($1);}
        | RETURN ';'                          {$$=newLeaf($1);}
        | RETURN expression ';'                          {$$=addSibling(newLeaf($1), $2);}
        ;

program
        : external_declaration                   {$$=symRoot=$1;strcpy(scope, "Global");}
        | program external_declaration    {$$=symRoot=addSibling(addNext(newLeaf("program"),$1),addNext(newLeaf("extDecl"),$2));strcpy(scope, "Global");}
        ;

external_declaration
        : function_definition         {$$=addSibling(newLeaf("func"),$1);}
        | declaration                   {$$=$1;}
        ;

function_definition
        : declaration_specifiers declarator declaration_list compound_statement  
	                                                                  /* {$$=addSibling($1, addSibling($2, addSibling($3, $4)));}*/
									  
                {$$=addSibling(addNext(newLeaf("decSpec"),$1),
		                       addSibling(addNext(newLeaf("dectr"),$2),
				                                    addSibling(addNext(newLeaf("decLst"),$3), 
								                addNext(newLeaf("cmpStmt"),$3))));
			}
        | declaration_specifiers declarator compound_statement
	                                                                /*   {$$=addSibling($1, addSibling($2, $3));}*/
					 {$$=addSibling(addNext(newLeaf("decSpec"),$1),
					                            addSibling(addNext(newLeaf("dectr"),$2),
								                       addNext(newLeaf("cmpStmt"),$3)));
						}	
        | declarator declaration_list compound_statement
	                                                             /*      {$$=addSibling($1, addSibling($2, $3));}*/
		{$$=addSibling(addNext(newLeaf("dectr"),$1),
		                      addSibling(addNext(newLeaf("decLst"),$2),
				                   addNext(newLeaf("cmpStmt"),$3)));
			}	
        | declarator compound_statement
	                                                      /*             {$$=addSibling($1, $2);}*/
	              {$$=addSibling(addNext(newLeaf("dectr"),$1),
		                            addNext(newLeaf("cmpStmt"),$2));
			}
       // | error ';'  {$$=symRoot=NULL;yyerrok;}
        ;


%%
#include <stdio.h>
#include "c-.yy.c"
//extern char yytext[];

yyerror(s)
char *s;
{
                 //  numError++;
        //fprintf (stderr, "%s in line %i\n", s, currLine);
                  // printf ("c- ERROR in line %i: parsing error before token \"%s\" .\n", yytext, currLine);
		 printf ("ERROR @(%d,%d) : parsing error before token \"%s\"\n", currLine, column,yylval);
}

 
int main( argc, argv)
int argc;
char **argv;
{
	char input;
	extern int yydebug; 
	++argv, --argc;  /* skip over program name */
	int i=0;
	char buf[255], c_filename[255];
	int s_flag=0, p_flag=0;
	int t;
	for(i=0; i<argc; i++){
		if(argv[i][0]=='-'){
			switch(argv[i][1]){
			case 's':
				s_flag=1;
				break;
			case 'p':
				p_flag=1;
				break;
			}
			continue;
		}
		strcpy(c_filename, argv[i]);		
	}  
	if(argc>0){
		yyin = fopen( c_filename, "r");
		if(yyin==NULL){
			printf("can open input file\n");
			exit(0);
		}
	}
    	else{
		printf("Default usage: ./a.out test.cc -s\n");
		yyin = stdin;
    	}
           
    yydebug = 0;
    initGlobalVal();
    yyparse();
    //if(p_flag) printParseTree(symRoot);
    //if(s_flag) printSymbolTable();
    if(yynerrs==0){
            empty();
            typeCheck(symRoot);
	    //printf("finished!\n");
	    if(typeErrs==0){
            	if(p_flag) printParseTree(symRoot);
            	if(s_flag) printSymbolTable();
	    }else{
            	printf("%d error(s) found totally\n", typeErrs); 
	   	exit (0);	    
	    }	    
    }else{
            printf("%d error(s) found totally\n", yynerrs); 
	    exit (0);
   }	    

    strcpy(source_filename,c_filename);
    for(i=strlen(source_filename)-1;i>0;i--){
      if(source_filename[i]=='.')
	source_filename[i]='\0';
    }

    strcpy( literals_filename, strcat(strcpy(buf, source_filename), ".literals") );
    literals_file = fopen( literals_filename, "w" );
    output_literal_file( literals_file,strCount, literals );    
    fclose( literals_file );

    strcpy( assembler_filename, strcat(strcpy(buf, source_filename), ".S") );
    strcpy( object_code_filename, strcat(strcpy(buf, source_filename), ".o") );

    assembler_file = fopen( assembler_filename, "w" );
    
    output_start( assembler_file, literals_filename );
    empty(); // empty the stack
    code_gen(assembler_file, symRoot);
    //output_end( assembler_file);
    fclose(assembler_file);
  
    char buff[40];
    sprintf(buff,"as -o%s %s", object_code_filename, assembler_filename);
    system(buff);
    
    sprintf(buff,"ld -o%s %s %s", source_filename, object_code_filename,"ishow.o fshow.o");
    system(buff);    
    
    return 0;
}