private byte[] GetInstructionBytes(IList<AssemblerMessage> messages, IDictionary<string, byte> labels, ParsedInstruction parsedInstruction)
{
if (parsedInstruction.OpCodeInfo.InstructionSize > 1)
{
var generator = parsedInstruction.OpCodeInfo.InstructionGenerator;
if (generator == null)
throw new Exception("The generator was null!!!!");
var context = new FinalAssembleContext(labels, messages, parsedInstruction);
var argumentBytes = generator.GenerateInstruction(context);
if (argumentBytes == null)
return null;
if (argumentBytes.Length != parsedInstruction.OpCodeInfo.InstructionSize - 1)
{
messages.Add(new AssemblerMessage(ErrorLevel.Error, string.Format("The number of bytes produced does not match the instruction size.")));
return null;
}
return new byte[] { parsedInstruction.OpCodeInfo.OpCode }.Concat(argumentBytes).ToArray();
}
else
{
return new byte[] {parsedInstruction.OpCodeInfo.OpCode};
}
}
public Pass1Result(IDictionary<string, byte> labels, ParsedInstruction[] parsedInstructions)
{
if (labels == null)
throw new ArgumentNullException("labels");
if (parsedInstructions == null)
throw new ArgumentNullException("parsedInstructions");
this.Labels = labels;
this.ParsedInstructions = parsedInstructions;
}
public FinalAssembleContext(IDictionary<string, byte> labels,
IList<AssemblerMessage> messages,
ParsedInstruction parsedInstruction)
{
if (labels == null)
throw new ArgumentNullException("labels");
if (messages == null)
throw new ArgumentNullException("messages");
if (parsedInstruction == null)
throw new ArgumentNullException("parsedInstruction");
_labels = labels;
_messages = messages;
_parsedInstruction = parsedInstruction;
}
private Pass1Result Pass1(IList<AssemblerMessage> messages, SourceLine[] sourceLines)
{
if (messages == null)
throw new NullReferenceException("messages");
if (sourceLines == null)
throw new NullReferenceException("sourceLines");
byte currentLocation = 0;
var parsedInstructions = new List<ParsedInstruction>(sourceLines.Length);
Dictionary<string, byte> labels = new Dictionary<string, byte>();
foreach (var sourceLine in sourceLines)
{
//Ditch the whitespace
var cleanedLine = sourceLine.Line.RemoveWhitespace();
if (cleanedLine.StartsWith(":"))
{
//This is a label
string labelName = LabelNameGetter.GetLabelName(cleanedLine);
if (string.IsNullOrWhiteSpace(labelName))
{
messages.Add(new AssemblerMessage(ErrorLevel.Error, string.Format("Invalid label on line {0}", sourceLine.LineNumber), sourceLine.LineNumber));
}
else
{
labels.Add(labelName, currentLocation);
}
}
else
{
//This out to be a bloody instruction
var parts = cleanedLine.Split(',');
//This is the number of arguments specified
var numberOfArgumentsSpecified = parts.Length - 1;
//Get the instruction name
string instructionName = parts[0];
//Attempt to get the op code info
var opCodeInfo = OpCodeFactory.GetOpCodeInfo(parts[0]);
//Check to see
if (opCodeInfo == null)
{
messages.Add(new AssemblerMessage(ErrorLevel.Error, string.Format("Invalid instruction '{0}' on line {1}", instructionName, sourceLine.LineNumber), sourceLine.LineNumber));
}
else
{
if (numberOfArgumentsSpecified != opCodeInfo.NumberOfArguments)
{
messages.Add(new AssemblerMessage(ErrorLevel.Error, string.Format("The instruction '{0}' takes {1} parameters but {2} were specified.", opCodeInfo.AssemblerKeyword, opCodeInfo.NumberOfArguments, numberOfArgumentsSpecified)));
}
else
{
//Get the arguments
var arguments = parts.Skip(1).ToArray();
//Create the parsed instruction
var parsedInstruction = new ParsedInstruction(sourceLine, arguments, opCodeInfo);
parsedInstructions.Add(parsedInstruction);
//Move the current location so that labels can be correctly set.
currentLocation += opCodeInfo.InstructionSize;
}
}
}
}
return new Pass1Result(labels, parsedInstructions.ToArray());
}
