public override void Parse()
{
var token = NextToken();
if ((PascalTokenType)token.m_Type == PascalTokenType.Const)
{
var const_parser = new ConstDeclarationParser(this);
const_parser.Parse();
}
//TODO: error?
token = CurrentToken();
if ((PascalTokenType)token.m_Type == PascalTokenType.Variable)
{
var var_parser = new VariableDeclarationParser(this);
var_parser.Parse();
}
//
CodeGenerator.Emit(Operation.Jump, 0, 0);//default 0
int current = CodeGenerator.m_Code.Count - 1;
//
for (; ;)
{
token = CurrentToken();
if ((PascalTokenType)token.m_Type == PascalTokenType.Procedure)
{
//
var proceduer_parser = new ProcedureDeclarationParser(this);
proceduer_parser.Parse();
}
else
{
break;
}
}
//TODO:
SymbolTablePrinter.RecordSymbolTable(m_SymbolTableStack.GetLocalSymbolTable());
//
CodeGenerator.Refine(current, CodeGenerator.m_Code.Count);
//allocate variables
var local = m_SymbolTableStack.GetLocalSymbolTable();
CodeGenerator.Emit(Operation.Allocate, 0, (local as SymbolTable).m_VariableAmount);
//
token = CurrentToken();
var statement_parser = new StatementParser(this);
statement_parser.Parse();
//
CodeGenerator.Emit(Operation.Return);
}
public override void Parse()
{
// <condition> JPC <then-statement1> JMP label_JPC <else-statement> label_JMP
try
{
ConsumeCurrentToken();//skip if
var condition_parser = new ConditionParser(this);
condition_parser.Parse();
var token = CurrentToken();
if (token.m_Text != "then")
{
//TODO: error
ErrorReporter.RecordError(22, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
ConsumeCurrentToken();//skip then
//
CodeGenerator.Emit(Operation.ConditionalJump, 0, 0); //default 0
int JPC = CodeGenerator.m_Code.Count - 1; //label1 is the address of JPC 0 ...
//
var statement_parser = new StatementParser(this);
statement_parser.Parse();
CodeGenerator.Emit(Operation.Jump, 0, 0); //default 0
int JMP = CodeGenerator.m_Code.Count - 1; //label1 is the address of JMP 0 ...
int label_JPC = CodeGenerator.m_Code.Count;
CodeGenerator.Refine(JPC, label_JPC);
token = CurrentToken();
if (token.m_Text == "else")
{
ConsumeCurrentToken();//skip then
statement_parser = new StatementParser(this);
statement_parser.Parse();
int label_JMP = CodeGenerator.m_Code.Count;
CodeGenerator.Refine(JMP, label_JMP);
}
else
{
CodeGenerator.Refine(JMP, label_JPC);
}
}
catch (Exception)
{
}
}
public override void Parse()
{
ConsumeCurrentToken();//skip while
int label_true = CodeGenerator.m_Code.Count;
var condition_parser = new ConditionParser(this);
condition_parser.Parse();
if (condition_parser.IsValid == false)
{
return;
}
var token = CurrentToken();
if (token.m_Text != "do")
{
//TODO: error
}
ConsumeCurrentToken();//skip do
//
int label_condition_jump = CodeGenerator.m_Code.Count;
CodeGenerator.Emit(Operation.ConditionalJump, 0, 0);//default 0
//
var statement_parser = new StatementParser(this);
statement_parser.Parse();
//
//
CodeGenerator.Emit(Operation.Jump, 0, label_true);//default 0
int label_false = CodeGenerator.m_Code.Count;
CodeGenerator.Refine(label_condition_jump, label_false);
}
private void OnParse()
{
var statement_parser = new StatementParser(this);
statement_parser.Parse();
}
