void AddToLabelList(Symbol s)
{
if (codegen.CurrentSection == SectionType.InitializedData)
{
labelList_ID.Add(s);
}
else if (codegen.CurrentSection == SectionType.UninitializedData)
{
labelList_UD.Add(s);
}
}
int GetTerm(out Symbol x)
{
Token op;
int n;
Symbol y;
n = GetFactor(out x);
while (sym == Token.Times || sym == Token.Slash || sym == Token.And)
{
op = sym;
scanner.Get(out sym);
if (op == Token.Times)
{
n *= GetFactor(out y);
}
else if (op == Token.Slash)
{
n /= GetFactor(out y);
}
else
{
n &= GetFactor(out y);
}
if (x != null || y != null)
scanner.Mark(ErrorType.InvalidOperationForRelocatableSymbol);
}
return n;
}
int GetFactor(out Symbol x)
{
int n;
uint w;
Symbol y;
string id;
x = null;
if (sym == Token.Not)
{
scanner.Get(out sym);
n = ~GetFactor(out x);
}
else if (sym == Token.Number)
{
unchecked { n = (int)scanner.Number; }
scanner.Get(out sym);
}
else if (sym == Token.Ident)
{
id = scanner.Name.ToUpper();
if (id == "LO" || id == "HI")
{
scanner.Get(out sym);
if (sym != Token.Lparen)
{
scanner.Mark(ErrorType.LeftParenExpected);
n = 0;
}
scanner.Get(out sym);
w = (uint)GetExpression(out y);
if (sym != Token.Rparen)
scanner.Mark(ErrorType.RightParenExpected);
else
scanner.Get(out sym);
if (y != null)
scanner.Mark(ErrorType.InvalidOperationForRelocatableSymbol);
if (id == "HI")
n = (int)CodeGen.GetHighPart(w);
else
n = (int)CodeGen.GetLowPart(w);
}
else
{
y = symtab.Find(scanner.Name);
if (y == null)
{
scanner.Mark(ErrorType.UndefinedIdentifier);
n = 0;
}
else
{
if ((y.type == SymbolType.Label || y.type == SymbolType.Import))
{
x = y;
}
scanner.Get(out sym);
n = (int)y.val;
}
}
}
else if (sym == Token.Lparen)
{
scanner.Get(out sym);
n = GetExpression(out y);
if (sym != Token.Rparen)
scanner.Mark(ErrorType.RightParenExpected);
else
scanner.Get(out sym);
}
else
{
scanner.Mark(ErrorType.IllegalExpression);
n = 0;
}
return n;
}
int GetExpression(out Symbol x)
{
bool neg;
Token op;
int n;
Symbol y;
neg = false;
if (sym == Token.Plus)
scanner.Get(out sym);
else if (sym == Token.Minus)
{
neg = true;
scanner.Get(out sym);
}
n = GetTerm(out x);
if (neg)
{
n = -n;
if (x != null)
scanner.Mark(ErrorType.InvalidOperationForRelocatableSymbol);
}
while (sym == Token.Plus || sym == Token.Minus || sym == Token.Or)
{
op = sym;
scanner.Get(out sym);
if (op == Token.Plus)
{
n += GetTerm(out y);
if (x == null)
x = y;
else if (y != null)
scanner.Mark(ErrorType.InvalidOperationBetweenRelocatableSymbols);
}
else if (op == Token.Minus)
{
n -= GetTerm(out y);
if (y != null)
{
if (x == null)
scanner.Mark(ErrorType.InvalidOperationForRelocatableSymbol);
else if (x.type == SymbolType.Import || y.type == SymbolType.Import)
scanner.Mark(ErrorType.InvalidOperationBetweenRelocatableSymbols);
else
x = null;
}
}
else
{
n |= GetTerm(out y);
if (x != null || y != null)
scanner.Mark(ErrorType.InvalidOperationForRelocatableSymbol);
}
}
return n;
}
public Symbol InsertLabel(string name, uint val, SectionType st)
{
Symbol s;
if (tab.ContainsKey(name))
{
s = tab[name];
if (s.type == SymbolType.Pending)
{
s.type = SymbolType.Label;
s.sectType = st;
s.val = val;
}
else
{
s = null;
scanner.Mark(ErrorType.DuplicatedDefinition);
}
}
else
{
s = new Symbol(SymbolType.Label, name, val, st);
tab.Add(name, s);
}
return s;
}
public void InsertImport(string name)
{
Symbol s;
if (tab.ContainsKey(name))
{
scanner.Mark(ErrorType.DuplicatedDefinition);
}
else
{
s = new Symbol(SymbolType.Import, name, 0, SectionType.Null);
tab.Add(name, s);
}
}