public override void Parse()
{
try
{
ConsumeCurrentToken(); //skip var
OnParse();
for (; ;)
{
var token = CurrentToken();
if (token.m_Text == ",")
{
ConsumeCurrentToken();//skip ,
OnParse();
}
else if (token.m_Text == ";")
{
ConsumeCurrentToken();//skip ;
break;
}
else
{
//TODO: error
ErrorReporter.RecordError(0, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
}
}
catch (Exception)
{
}
}
public void OnParse()
{
//
var local = m_SymbolTableStack.GetLocalSymbolTable();
//
var token = CurrentToken();
if ((token as PascalToken).GetType() != PascalTokenType.Identifier)
{
//TODO: error
ErrorReporter.RecordError(16, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
var result = m_SymbolTableStack.LookupLocal(token.m_Text);
if (result != null)
{
//TODO: error
ErrorReporter.RecordError(17, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
// if not in table
local.Enter(token.m_Text);
var item = local.Lookup(token.m_Text) as SymbolTableEntry;
item.SetAttribute(SymbolTableAttributeKeyType.Offset, (local as SymbolTable).m_VariableAmount + 3);
item.SetAttribute(SymbolTableAttributeKeyType.Type, SymbolTableEntryType.Variable);
++(local as SymbolTable).m_VariableAmount;
ConsumeCurrentToken();//skip to next
}
public override void Parse()
{
var token = CurrentToken();
var result = m_SymbolTableStack.Lookup(token.m_Text);
if (result == null)
{
//TODO: error
ErrorReporter.RecordError(12, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
else
{
var type = (SymbolTableEntryType)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Type);
if (type != SymbolTableEntryType.Variable)
{
//TODO: error
ErrorReporter.RecordError(13, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
}
var current_nesting_level = m_SymbolTableStack.GetCurrentNestingLevel();
var reference_nesting_level = result.GetSymbolTable().GetNestingLevel();
int offset = (int)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Offset);
token = NextToken();
if (token.m_Text != ":=")
{
//TODO: error
ErrorReporter.RecordError(11, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
ConsumeCurrentToken();//skip :=
var expression_parser = new ExpressionParser(this);
expression_parser.Parse();
//token = CurrentToken();
//if (token.m_Text != ";")
//{
// //TODO: error
//}
//ConsumeCurrentToken();
CodeGenerator.Emit(Operation.Store, current_nesting_level - reference_nesting_level, offset);
}
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 void OnParse()
{
//
var local = m_SymbolTableStack.GetLocalSymbolTable();
//
var token = CurrentToken();
if ((token as PascalToken).GetType() != PascalTokenType.Identifier)
{
//TODO: error
ErrorReporter.RecordError(18, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
var result = m_SymbolTableStack.LookupLocal(token.m_Text);
if (result != null)
{
//TODO: error
ErrorReporter.RecordError(19, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
// if not in table
local.Enter(token.m_Text);
var item = local.Lookup(token.m_Text) as SymbolTableEntry;
// skip =
token = NextToken();
if (token.m_Text != "=")
{
//TODO: error
ErrorReporter.RecordError(20, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
token = NextToken();
if ((token as PascalToken).GetType() != PascalTokenType.Unsigned)
{
//TODO: error
ErrorReporter.RecordError(21, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
item.SetAttribute(SymbolTableAttributeKeyType.ConstantValue, token.m_Value);
item.SetAttribute(SymbolTableAttributeKeyType.Type, SymbolTableEntryType.Constant);
ConsumeCurrentToken();// skip const value
}
public override void Parse()
{
ConsumeCurrentToken(); //skip call
var token = CurrentToken();
if ((PascalTokenType)token.m_Type != PascalTokenType.Identifier)
{
//TODO: error
ErrorReporter.RecordError(6, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
var result = m_SymbolTableStack.Lookup(token.m_Text);
//TODO: if type is proceduer? what happen if identifier name is the same as procedure?
if (result == null)
{
//TODO: error
ErrorReporter.RecordError(7, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
else
{
var type = (SymbolTableEntryType)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Type);
if (type != SymbolTableEntryType.Procedure)
{
//TODO: error
ErrorReporter.RecordError(8, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
}
var current_nesting_level = m_SymbolTableStack.GetCurrentNestingLevel();
var reference_nesting_level = result.GetSymbolTable().GetNestingLevel();
int address = (int)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Address);
CodeGenerator.Emit(Operation.Call, current_nesting_level - reference_nesting_level, address);
//
token = NextToken();//skip proceduer name
//if (token.m_Text != ";")
//{
// //TODO: error
// ErrorReporter.RecordError(9, m_Scanner.m_CurrentToken.m_LineNumber);
// return;
//}
}
public override void Parse()
{
var token = CurrentToken();
if (token.m_Text == "odd")
{
try
{
ParseOdd();
}
catch (Exception)
{
}
return;
}
// parse one expression
var expression1_parser = new ExpressionParser(this);
expression1_parser.Parse();
// parse operator
token = CurrentToken();
Operation op = Operation.Null;
try
{
op = m_TokenOperationMap[(PascalTokenType)token.m_Type];
}
catch (Exception)
{
//TODO: error
ErrorReporter.RecordError(10, m_Scanner.m_CurrentToken.m_LineNumber);
IsValid = false;
return;
}
ConsumeCurrentToken();//skip operator
// parse another expression
var expression2_parser = new ExpressionParser(this);
expression2_parser.Parse();
//
CodeGenerator.Emit(op);
}
public override void Parse()
{
try
{
ParseHead();
//
(m_SymbolTableStack as SymbolTableStack).Push();
var program_parser = new ProgramParser(this);
program_parser.Parse();
(m_SymbolTableStack as SymbolTableStack).Pop();
var token = CurrentToken();
if (token.m_Text != ";")
{
//TODO: error
ErrorReporter.RecordError(9, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
//
ConsumeCurrentToken();//skip ;
}
catch (Exception)
{
}
//if ((PascalTokenType)token.m_Type == PascalTokenType.Procedure)
//{
// //
// (m_SymbolTableStack as SymbolTableStack).Push();
// var proceduer_parser = new ProcedureParser(this);
// proceduer_parser.Parse();
// //
// SymbolTablePrinter.RecordSymbolTable(m_SymbolTableStack.GetLocalSymbolTable());
// (m_SymbolTableStack as SymbolTableStack).Pop();
//}
}
private bool OnParse()
{
var token = CurrentToken();
//
var result = m_SymbolTableStack.Lookup(token.m_Text);
if (result == null)
{
//TODO: error
ErrorReporter.RecordError(4, m_Scanner.m_CurrentToken.m_LineNumber);
return(false);
}
var type = (result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Type);
switch (type)
{
case SymbolTableEntryType.Variable:
var current_nesting_level = m_SymbolTableStack.GetCurrentNestingLevel();
var reference_nesting_level = result.GetSymbolTable().GetNestingLevel();
int offset = (int)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Offset);
CodeGenerator.Emit(Operation.LoadVariable, current_nesting_level - reference_nesting_level, offset);
CodeGenerator.Emit(Operation.Write);
break;
case SymbolTableEntryType.Constant:
int value = (int)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.ConstantValue);
CodeGenerator.Emit(Operation.LoadLiteral, 0, value);
CodeGenerator.Emit(Operation.Write);
break;
default:
//TODO: error
ErrorReporter.RecordError(2, m_Scanner.m_CurrentToken.m_LineNumber);
return(false);
}
ConsumeCurrentToken();//skip current variable
return(true);
}
private void ParseHead()
{
ConsumeCurrentToken(); //skip procedure
var token = CurrentToken();
if ((PascalTokenType)token.m_Type != PascalTokenType.Identifier)
{
//TODO: error
ErrorReporter.RecordError(14, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
// enter procedure in symbol table
// if not in table
var result = m_SymbolTableStack.LookupLocal(token.m_Text);
if (result != null)
{
//TODO: error
ErrorReporter.RecordError(15, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
m_SymbolTableStack.EnterLocalSymbolTable(token.m_Text);
var item = m_SymbolTableStack.LookupLocal(token.m_Text) as SymbolTableEntry;
item.SetAttribute(SymbolTableAttributeKeyType.Address, CodeGenerator.m_Code.Count + 1);
item.SetAttribute(SymbolTableAttributeKeyType.Type, SymbolTableEntryType.Procedure);
token = NextToken();//skip proceduer name
if (token.m_Text != ";")
{
//TODO: error
ErrorReporter.RecordError(9, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
}
public override void Parse()
{
try
{
ConsumeCurrentToken();//skip repeat
int label_JPC = CodeGenerator.m_Code.Count;
OnParse();
for (; ;)
{
var token = CurrentToken();
if (token.m_Text == ";")
{
ConsumeCurrentToken();//skip ;
OnParse();
}
else if (token.m_Text == "until")
{
ConsumeCurrentToken();//skip until
var condition_parser = new ConditionParser(this);
condition_parser.Parse();
CodeGenerator.Emit(Operation.ConditionalJump, 0, label_JPC);
return;
}
else
{
//TODO: error
ErrorReporter.RecordError(0, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
}
}
catch (Exception)
{
}
}
public override void Parse()
{
ConsumeCurrentToken();//skip read
//
var token = CurrentToken();
if (token.m_Text != "(")
{
//TODO: error
ErrorReporter.RecordError(1, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
ConsumeCurrentToken();//skip (
for (; ;)
{
token = CurrentToken();
if (token.m_Text == ";")
{
//TODO: error
ErrorReporter.RecordError(5, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
else if (token.m_Text == ")")
{
ConsumeCurrentToken();//skip )
break;
}
else if ((token as PascalToken).GetType() != PascalTokenType.Identifier)
{
//TODO: error
ErrorReporter.RecordError(3, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
if (OnParse() != true)
{
return;
}
token = CurrentToken();
if (token.m_Text == ",")
{
ConsumeCurrentToken();//skip ,
if (OnParse() != true)
{
return;
}
}
else if (token.m_Text == ")")
{
ConsumeCurrentToken();//skip )
return;
}
else
{
//TODO: error
ErrorReporter.RecordError(0, m_Scanner.m_CurrentToken.m_LineNumber);
return;
}
}
}
private void ParseFactor()
{
var token = CurrentToken();
switch (token.m_Type)
{
case PascalTokenType.Unsigned:
int value = (int)token.m_Value;
CodeGenerator.Emit(Operation.LoadLiteral, 0, value);
ConsumeCurrentToken();
break;
case PascalTokenType.Identifier:
var result = m_SymbolTableStack.Lookup(token.m_Text);
if (result == null)
{
//TODO: error
ErrorReporter.RecordError(4, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
var type = (result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Type);
switch (type)
{
case SymbolTableEntryType.Constant:
int const_value = (int)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.ConstantValue);
CodeGenerator.Emit(Operation.LoadLiteral, 0, const_value);
break;
case SymbolTableEntryType.Variable:
var current_nesting_level = m_SymbolTableStack.GetCurrentNestingLevel();
var reference_nesting_level = result.GetSymbolTable().GetNestingLevel();
int offset = (int)(result as SymbolTableEntry).GetAttribute(SymbolTableAttributeKeyType.Offset);
CodeGenerator.Emit(Operation.LoadVariable, current_nesting_level - reference_nesting_level, offset);
break;
default:
break;
}
ConsumeCurrentToken();
break;
case PascalTokenType.LeftParenthesis:
ConsumeCurrentToken(); //skip (
var expression_parser = new ExpressionParser(this);
expression_parser.ParseExpression();
token = CurrentToken();
if (token.m_Text != ")")
{
//TODO: error
ErrorReporter.RecordError(5, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
ConsumeCurrentToken(); //skip )
break;
default:
//TODO: error
ErrorReporter.RecordError(0, m_Scanner.m_CurrentToken.m_LineNumber);
throw new Exception();
}
}
public override void Parse()
{
try
{
var token = CurrentToken();
switch (token.m_Type)
{
case PascalTokenType.Begin:
var compound_parser = new CompoundParser(this);
compound_parser.Parse();
break;
case PascalTokenType.Identifier:
var assignment_parser = new AssignmentParser(this);
assignment_parser.Parse();
break;
case PascalTokenType.If:
var if_parser = new IfStatementParser(this);
if_parser.Parse();
break;
case PascalTokenType.Call:
var procedure_parser = new ProcedureParser(this);
procedure_parser.Parse();
break;
case PascalTokenType.While:
var while_parser = new WhileStatementParser(this);
while_parser.Parse();
break;
case PascalTokenType.Read:
var read_parser = new ReadParser(this);
read_parser.Parse();
break;
case PascalTokenType.Write:
var write_parser = new WriteParser(this);
write_parser.Parse();
break;
case PascalTokenType.Repeat:
var repeat_parser = new RepeatStatementParser(this);
repeat_parser.Parse();
break;
//case PascalTokenType.Semicolon:
// ConsumeCurrentToken();
// break;
default:
if (!FollowStatement.Contains(token.m_Text))
{
//TODO: error
ErrorReporter.RecordError(0, m_Scanner.m_CurrentToken.m_LineNumber, ",possibility: missing ;");
throw new Exception();
}
break;
}
}
catch (Exception)
{
}
}
