public static bool IsReservedWord(string str)
{
if (str == null)
{
return(false);
}
if (InstructionSet.IsConditionFlag(str) ||
InstructionSet.IsValidInstructionName(str) ||
InstructionSet.IsValidRegister(str))
{
return(true);
}
switch (str.ToUpperInvariant())
{
case "ORG":
case "SEEK":
case "END":
case "INCLUDE":
case "INCBIN":
case "EQU":
case "DB":
case "DEFB":
case "DEFM":
case "DW":
case "DEFW":
case "DS":
case "DEFS":
case "IF":
case "ENDIF":
case "ELSE":
case "ELSEIF":
case "PROC":
case "ENDP":
case "MACRO":
case "ENDM":
case "DEFBITS":
case "BITMAP":
case "ENDB":
case "ERROR":
case "WARNING":
case "RADIX":
case "STRUCT":
case "ENDS":
case "BYTE":
case "WORD":
return(true);
}
return(false);
}
ExprNode ParseLeaf()
{
var pos = _tokenizer.TokenPosition;
// Number literal?
if (_tokenizer.Token == Token.Number)
{
var node = new ExprNodeNumberLiteral(pos, _tokenizer.TokenNumber);
_tokenizer.Next();
return(node);
}
// String literal?
if (_tokenizer.Token == Token.String)
{
var str = _tokenizer.TokenString;
_tokenizer.Next();
return(new ExprNodeStringLiteral(pos, str));
}
// Defined operator?
if (_tokenizer.TrySkipIdentifier("defined"))
{
_tokenizer.SkipToken(Token.OpenRound);
_tokenizer.CheckToken(Token.Identifier);
var node = new ExprNodeIsDefined(pos, _tokenizer.TokenString);
_tokenizer.Next();
_tokenizer.SkipToken(Token.CloseRound);
return(node);
}
// Sizeof operator?
if (_tokenizer.TrySkipIdentifier("sizeof"))
{
_tokenizer.SkipToken(Token.OpenRound);
var node = new ExprNodeSizeOf(pos, ParseExpression());
_tokenizer.SkipToken(Token.CloseRound);
return(node);
}
// Identifier
if (_tokenizer.Token == Token.Identifier)
{
// Special identifier
if (InstructionSet.IsConditionFlag(_tokenizer.TokenString) ||
InstructionSet.IsValidRegister(_tokenizer.TokenString))
{
var node = new ExprNodeRegisterOrFlag(pos, _tokenizer.TokenString);
_tokenizer.Next();
return(node);
}
else
{
var node = new ExprNodeIdentifier(pos, _tokenizer.TokenString);
_tokenizer.Next();
if (_tokenizer.Token == Token.Period)
{
ExprNode retNode = node;
while (_tokenizer.TrySkipToken(Token.Period))
{
_tokenizer.CheckToken(Token.Identifier);
retNode = new ExprNodeMember(_tokenizer.TokenPosition, _tokenizer.TokenString, retNode);
_tokenizer.Next();
}
return(retNode);
}
if (_tokenizer.Token == Token.OpenRound)
{
node.Arguments = ParseArgumentList();
}
return(node);
}
}
// Parens?
if (_tokenizer.TrySkipToken(Token.OpenRound))
{
var node = ParseExpressionList();
_tokenizer.SkipToken(Token.CloseRound);
return(node);
}
// Array?
if (_tokenizer.Token == Token.OpenSquare)
{
return(ParseOrderedStructData());
}
// Map?
if (_tokenizer.Token == Token.OpenBrace)
{
return(ParseNamedStructData());
}
throw new CodeException($"syntax error in expression: {Tokenizer.DescribeToken(_tokenizer.Token, _tokenizer.TokenRaw)}", _tokenizer.TokenPosition);
}