Semantic Analyzer

Specifications

	
SemanticAnalyzer.cpp:SemanticAnalyzer  	
SemanticAnalyzer.h 	

SemanticRecord.cpp:Operating of SymbolRecord  	
SemanticRecord.h 	

Source Listing

Some example of SemanticAnalyzer code

bool SemanticAnalyser::insertSymbol(SemanticRecord& record)
{
	while (record.size() > 0 )
	{
		if (record.showNextOperandAs()){
			LexemeOperand* nextOp = record.showNextOperandAs();
			assert(nextOp);
			insertSymbol(nextOp->getLexeme(), nextOp->type());
		}
		else{
			assert(false);
			return false;
		}
		delete record.getNextOperandPointer();
	}
	return true;
}

void SemanticAnalyser::whileStatementPostbody(int repeatLabel, int exitLabel)
{
	_outFile << "BR L" << repeatLabel << " \n";
	_outFile << "L" << exitLabel << ":\n";

	if (ENABLE_DEBUGGING)
		_outFile << "; end 'while' loop \n\n";
}


void SemanticAnalyser::forBegin(int& beginCondition,int& exitLoop, SemanticRecord& controlVars)
{
	//we need to allocate the space for the variables
	
	LexemeOperand lexOp1 = controlVars.getNextOperandAsLexeme();
	MachineVal initVal = generateMachineValue(lexOp1.getLexeme());

	//we dont use this for anything because this is on top of the stack
	Operand lexOp2 = controlVars.getNextOperand();
	//MachineVal assignedVal = generateMachineValue(lexOp2.getLexeme());

	LexemeOperand lexOp3 = controlVars.getNextOperandAsLexeme();
	MachineVal stepVal = generateMachineValue(lexOp3.getLexeme());
	//this should be a -1 or 1 depending on if
	//we are going up or down. 

	//this is on the stack as well so no neet to use it
	Operand lexOp4 = controlVars.getNextOperand();
	//MachineVal finalVal = generateMachineValue(lexOp4.getLexeme());

	controlVars.addOperand(new LexemeOperand( lexOp1));

	if (ENABLE_DEBUGGING)
		_outFile << "\n;         Begin 'for' loop\n";

	//int level = _currentTable->level() ;
	//
	//the intial value is on the stack and will be located at -1 offset current level
	_outFile << "PUSH " << initVal.value << " \n"; //for current value

	//set SP for offset into control vars
	//_outFile << "MOV SP D" << to_string(level) << " \n";


	//_outFile << "PUSH " << initVal.value << " \n";

	//change the loop variable to its assignment
	//_outFile << "PUSH " << "-3(D" << level << ") \n";
	_outFile << "PUSH " << "-3(SP) \n"; //one 
	_outFile << "POP " << initVal.value << " \n"; //zero

	//////////////////////////////////////
	////////////initialized
	//////////////////////////////////////

	//skip loop increment the first time
	int skipIncrement = getNextLabelVal();
	_outFile << "BR L" << skipIncrement << "\n";

	//begin the the condition check
	beginCondition = getNextLabelVal();
	_outFile << "L" << beginCondition << ": \n";

	//update the loop variable
	_outFile << "PUSH " << stepVal.value << " \n"; //one 
	_outFile << "PUSH " << initVal.value << " \n"; //one two
	_outFile << "ADDS " << " \n"; //one
	_outFile << "POP " << "-3(SP) \n";// -3  // zero
	_outFile << "PUSH " << "-3(SP) \n";//one
	_outFile << "POP " << initVal.value << " \n";//zero
	//loop variable updated

	_outFile << "L" << skipIncrement << ": \n";

	//check against limit
	_outFile << "PUSH " << "-3(SP) \n"; //one
	_outFile << "PUSH " << "-3(SP) \n"; //two
	//limit checked

	string compare = stepVal.value == "#-1" ? "CMPGES" : "CMPLES";
	_outFile << compare << "\n";

	exitLoop = getNextLabelVal();
	_outFile << "BRFS L" << to_string(exitLoop) << " \n";


	//if the step is negative we continue if greater than the condition
	//otherwise we want to continue if the value is less than the condition

}