/**
* Function representing the <oelem> productions
*/
attr RecursiveDescentParser::oelem(ParamList* &pList) {
attr retVal;
retVal.type = T_ERROR;
VariableEntry* vEntry = NULL;
if(errorCondition) return retVal;
if(token == TK_IDENTIFIER)
{
#if DEBUG_PARSER
std::cout << "<oelem> --> <var>\n";
#endif
vEntry = var();
}
else if(token == TK_NUM)
{
#if DEBUG_PARSER
std::cout << "<oelem> --> n\n";
#endif
//TODO fix memory leak here vEntry is never deleted
vEntry = new VariableEntry(T_INT, VA_SIMPLE);
vEntry->setAddress( symTab.getNextAddress() );
std::string val = token.getValue();
int litTabIndex = litTab.insert(atoi(val.c_str()));
iCode.threeAddressCode(vEntry->getAttr(), TAC_NUM_CONST, litTabIndex);
token = scanner->getToken();
}
else if(token == TK_CHAR_CONST)
{
#if DEBUG_PARSER
std::cout << "<oelem> --> 'c'\n";
#endif
//TODO fix memory leak here vEntry is never deleted
vEntry = new VariableEntry(T_CHAR, VA_SIMPLE);
vEntry->setAddress( symTab.getNextAddress() );
std::string val = token.getValue();
int litTabIndex = litTab.insert(val[1]);
iCode.threeAddressCode(vEntry->getAttr(), TAC_CHAR_CONST, litTabIndex);
token = scanner->getToken();
}
else
{
errorHandler();
}
if(vEntry) {
pList->push_back(vEntry);
retVal = vEntry->getAttr();
}
return retVal;
}
/**
* Function representing the <var> productions
*/
VariableEntry* RecursiveDescentParser::var() {
VariableEntry* ve=NULL;
if(errorCondition) return ve;
if(token == TK_IDENTIFIER)
{
#if DEBUG_PARSER
std::cout << "<var> --> i<var_prime>\n";
#endif
TableEntry* te=NULL;
if(!symTab.search(token, te))
{
std::stringstream errorMsg;
errorMsg << "Undeclared variable '" << token.getValue() << "'";
errorHandler(errorMsg.str(), token);
}
if(te && te->getEntryType()==TableEntry::VARIABLE)
{
ve = (VariableEntry*)te;
}
token = scanner->getToken();
attr varP = var_prime(ve);
if(ve && ve->getAttribute() == VA_ARRAY && varP.attrib == VA_SIMPLE) {
VariableEntry* vEntry = new VariableEntry(ve->getType(), VA_SIMPLE);
vEntry->setAddress( symTab.getNextAddress() );
iCode.threeAddressCode(vEntry->getAttr(), TAC_ADDRESS_OF, ve->getAttr(), varP);
ve = vEntry;
}
}
else
{
errorHandler();
}
return ve;
}
/**
* Function representing the <st_factor_ident> prods
*/
void RecursiveDescentParser::st_factor_ident(TableEntry* te) {
if(errorCondition) return;
if(token == TK_LEFT_PARENTHESES)
{
#if DEBUG_PARSER
std::cout << "<st_factor_ident> --> (<o_list>);\n";
#endif
Token leftParen = token;
token = scanner->getToken();
ParamList* pList = o_list();
if(te) {
if(te->getEntryType()!=TableEntry::FUNCTION) {
std::stringstream errorMsg;
errorMsg << "'" << te->getName() << "' is not a function";
errorHandler(errorMsg.str(), leftParen);
} else {
// now makes sure the lists match
FunctionEntry* fe = (FunctionEntry*)te;
if(pList) matchParameters(fe, pList, leftParen);
iCode.threeAddressCode(TAC_PARAM, pList);
iCode.threeAddressCode(
symTab.getNextAddress(), // throw away temporary
TAC_CALL,
fe->getLabel(),
fe->getParamCount()
);
}
} else {
std::stringstream errorMsg;
errorMsg << "Undeclared function";
errorHandler(errorMsg.str(), leftParen);
}
match(TK_RIGHT_PARENTHESES);
match(TK_SEMICOLON);
}
else if(token == TK_LEFT_BRACKET ||
token == TK_ASSIGNMENT)
{
#if DEBUG_PARSER
std::cout << "<st_factor_ident> --> <var_prime>=<exp>;\n";
#endif
VariableEntry* vEntry = (VariableEntry*)te;
Token startToken = token;
attr varAttr = var_prime(vEntry);
match(TK_ASSIGNMENT);
attr expAttr = exp();
if(expAttr.type != varAttr.type) {
std::stringstream errorMsg;
errorMsg << "Type mismatch variable '" << vEntry->getName() << "'";
errorHandler(errorMsg.str(), startToken);
}
if(varAttr.attrib == VA_ARRAY) {
std::stringstream errorMsg;
errorMsg << "Assignment error, array '" << vEntry->getName() << "' must be indexed.";
errorHandler( errorMsg.str(), startToken );
}
if(vEntry->getAttribute() == VA_ARRAY) {
// array addr value to assign index
iCode.threeAddressCode(vEntry->getAttr(), TAC_ASSIGN_TO_ADDRESS_AT, expAttr, varAttr);
} else {
iCode.threeAddressCode(vEntry->getAttr(), TAC_ASSIGN, expAttr);
}
match(TK_SEMICOLON);
}
else
{
errorHandler();
}
}