private void GenerateOutput(Stream target)
{
int numobjects = objects.Count;
LMSObject[] oarray = new LMSObject[numobjects];
// get all objects in order of their ID
foreach (LMSObject o in objects.Values)
{
oarray[o.id - 1] = o;
}
// create the byte codes in a temporary buffer and memorize positions
MemoryStream allbytecodes = new MemoryStream();
int totalheadersize = 16 + numobjects * 12;
for (int i = 0; i < numobjects; i++)
{
oarray[i].WriteBody(allbytecodes, totalheadersize + (int)allbytecodes.Length);
}
// write file header
target.WriteByte((byte)'L');
target.WriteByte((byte)'E');
target.WriteByte((byte)'G');
target.WriteByte((byte)'O');
DataWriter.Write32(target, totalheadersize + (int)allbytecodes.Length);
DataWriter.Write16(target, 0x0068);
DataWriter.Write16(target, numobjects);
DataWriter.Write32(target, globals.TotalBytes());
// write object headers
for (int i = 0; i < numobjects; i++)
{
oarray[i].WriteHeader(target);
// oarray[i].print();
// Console.ReadKey();
}
// write all object bodies
allbytecodes.WriteTo(target);
}
public void Assemble(Stream source, Stream target, List <String> errorList)
{
globals = new DataArea();
objects = new Dictionary <String, LMSObject>();
currentobject = null;
// read and process the input line by line
StreamReader reader = new StreamReader(source, System.Text.Encoding.ASCII);
String l = reader.ReadLine();
for (int linenumber = 1; l != null; l = reader.ReadLine(), linenumber++)
{
try {
ProcessLine(l);
}
catch (AssemblerException e)
{
errorList.Add("Error at line " + linenumber + ": " + e.Message);
}
}
if (currentobject != null)
{
errorList.Add("Unexpected end of file");
}
reader.Close();
try
{
GenerateOutput(target);
}
catch (AssemblerException e)
{
errorList.Add("Error at subcall integration: " + e.Message);
}
// globals.print();
// Console.ReadKey();
}
private void ProcessLine(String l)
{
List <String> tokens = TokenizeLine(l);
if (tokens.Count < 1)
{
return;
}
String first = tokens[0];
// Console.WriteLine(first);
// currently on top level
if (currentobject == null)
{
if (first.Equals("VMTHREAD"))
{
String name = FetchID(tokens, 1, true);
if (objects.ContainsKey(name))
{
// could have found object that was created because of forward reference
LMSObject lo = objects[name];
lo.StartCode();
currentobject = (LMSThread)lo; // make sure that this object is indeed a thread
}
else
{ // this is the first encounter of the name - create a new thread
currentobject = new LMSThread(name, objects.Count + 1);
currentobject.StartCode();
objects[name] = currentobject;
}
}
else if (first.Equals("SUBCALL"))
{
String name = FetchID(tokens, 1, true);
if (objects.ContainsKey(name))
{
// could have found the object that was created because of a forward reference
LMSObject lo = objects[name];
lo.StartCode();
currentobject = (LMSSubCall)lo; // make sure that this object is indeed a subcall
}
else
{
// this is the first encounter of the name - create a new subcall
LMSSubCall sc = new LMSSubCall(name, objects.Count + 1);
objects[name] = sc;
sc.StartCode();
currentobject = sc;
}
}
else if (first.Equals("DATA8"))
{
globals.Add(FetchID(tokens, 1, true), 1, 1, DataType.I8, false);
}
else if (first.Equals("DATA16"))
{
globals.Add(FetchID(tokens, 1, true), 2, 1, DataType.I16, false);
}
else if (first.Equals("DATA32"))
{
globals.Add(FetchID(tokens, 1, true), 4, 1, DataType.I32, false);
}
else if (first.Equals("DATAF"))
{
globals.Add(FetchID(tokens, 1, true), 4, 1, DataType.F, false);
}
else if (first.Equals("DATAS") || first.Equals("ARRAY8"))
{
globals.Add(FetchID(tokens, 1, false), 1, FetchNumber(tokens, 2, true), DataType.I8, false);
}
else if (first.Equals("ARRAY16"))
{
globals.Add(FetchID(tokens, 1, false), 2, FetchNumber(tokens, 2, true), DataType.I16, false);
}
else if (first.Equals("ARRAY32"))
{
globals.Add(FetchID(tokens, 1, false), 4, FetchNumber(tokens, 2, true), DataType.I32, false);
}
else if (first.Equals("ARRAYF"))
{
globals.Add(FetchID(tokens, 1, false), 4, FetchNumber(tokens, 2, true), DataType.F, false);
}
else
{
throw new AssemblerException("Unknown command: " + first);
}
}
// currently inside a structure element
else
{
DataArea locals = currentobject.locals;
if (first.Equals("}"))
{
// currentobject.print();
currentobject = null;
return;
}
if (first.Equals("SUBCALL")) // trying to create a subcall with multiple object IDs, but with the same code
{
if (!(currentobject is LMSSubCall))
{
throw new AssemblerException("Can not add subcall alias to non-subcall object");
}
String name = FetchID(tokens, 1, true);
if (objects.ContainsKey(name))
{
// could have found the object that was created because of a forward reference
LMSObject lo = objects[name];
((LMSSubCall)lo).SetImplementation((LMSSubCall)currentobject);
}
else
{
// this is the first encounter of the name - create a new subcall
LMSSubCall sc = new LMSSubCall(name, objects.Count + 1);
objects[name] = sc;
sc.SetImplementation((LMSSubCall)currentobject);
}
}
else if (first.Equals("DATA8"))
{
locals.Add(FetchID(tokens, 1, true), 1, 1, DataType.I8, false);
}
else if (first.Equals("DATA16"))
{
locals.Add(FetchID(tokens, 1, true), 2, 1, DataType.I16, false);
}
else if (first.Equals("DATA32"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.I32, false);
}
else if (first.Equals("DATAF"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.F, false);
}
else if (first.Equals("DATAS") || first.Equals("ARRAY8"))
{
locals.Add(FetchID(tokens, 1, false), 1, FetchNumber(tokens, 2, true), DataType.I8, false);
}
else if (first.Equals("ARRAY16"))
{
locals.Add(FetchID(tokens, 1, false), 2, FetchNumber(tokens, 2, true), DataType.I16, false);
}
else if (first.Equals("ARRAY32"))
{
locals.Add(FetchID(tokens, 1, false), 4, FetchNumber(tokens, 2, true), DataType.I32, false);
}
else if (first.Equals("ARRAYF"))
{
locals.Add(FetchID(tokens, 1, false), 4, FetchNumber(tokens, 2, true), DataType.F, false);
}
else if (first.Equals("IN_8"))
{
locals.Add(FetchID(tokens, 1, true), 1, 1, DataType.I8, true);
currentobject.MemorizeIOParameter(DataType.I8, AccessType.Read);
}
else if (first.Equals("IN_16"))
{
locals.Add(FetchID(tokens, 1, true), 2, 1, DataType.I16, true);
currentobject.MemorizeIOParameter(DataType.I16, AccessType.Read);
}
else if (first.Equals("IN_32"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.I32, true);
currentobject.MemorizeIOParameter(DataType.I32, AccessType.Read);
}
else if (first.Equals("IN_F"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.F, true);
currentobject.MemorizeIOParameter(DataType.F, AccessType.Read);
}
else if (first.Equals("IN_S"))
{
int n = FetchNumber(tokens, 2, true);
locals.Add(FetchID(tokens, 1, false), 1, n, DataType.I8, true);
currentobject.MemorizeStringIOParameter(n, AccessType.ReadMany);
}
else if (first.Equals("OUT_8"))
{
locals.Add(FetchID(tokens, 1, true), 1, 1, DataType.I8, true);
currentobject.MemorizeIOParameter(DataType.I8, AccessType.Write);
}
else if (first.Equals("OUT_16"))
{
locals.Add(FetchID(tokens, 1, true), 2, 1, DataType.I16, true);
currentobject.MemorizeIOParameter(DataType.I16, AccessType.Write);
}
else if (first.Equals("OUT_32"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.I32, true);
currentobject.MemorizeIOParameter(DataType.I32, AccessType.Write);
}
else if (first.Equals("OUT_F"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.F, true);
currentobject.MemorizeIOParameter(DataType.F, AccessType.Write);
}
else if (first.Equals("OUT_S"))
{
int n = FetchNumber(tokens, 2, true);
locals.Add(FetchID(tokens, 1, false), 1, n, DataType.I8, true);
currentobject.MemorizeStringIOParameter(n, AccessType.Write);
}
else if (first.Equals("IO_8"))
{
locals.Add(FetchID(tokens, 1, true), 1, 1, DataType.I8, true);
currentobject.MemorizeIOParameter(DataType.I8, AccessType.ReadWrite);
}
else if (first.Equals("IO_16"))
{
locals.Add(FetchID(tokens, 1, true), 2, 1, DataType.I16, true);
currentobject.MemorizeIOParameter(DataType.I16, AccessType.ReadWrite);
}
else if (first.Equals("IO_32"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.I32, true);
currentobject.MemorizeIOParameter(DataType.I32, AccessType.ReadWrite);
}
else if (first.Equals("IO_F"))
{
locals.Add(FetchID(tokens, 1, true), 4, 1, DataType.F, true);
currentobject.MemorizeIOParameter(DataType.F, AccessType.ReadWrite);
}
else if (first.Equals("IO_S"))
{
int n = FetchNumber(tokens, 2, true);
locals.Add(FetchID(tokens, 1, false), 1, n, DataType.I8, true);
currentobject.MemorizeStringIOParameter(n, AccessType.ReadWrite);
}
// calling a subcall object (maybe without having the declaration yet)
else if (first.Equals("CALL"))
{
String name = FetchID(tokens, 1, false);
LMSSubCall sc = null;
// the name is already known
if (objects.ContainsKey(name))
{
LMSObject o = objects[name];
if (!(o is LMSSubCall))
{
throw new AssemblerException("Trying to call an object that is not defined as a SUBCALL");
}
sc = (LMSSubCall)o;
}
// name is not known - create an empty subcall object right here
else
{
sc = new LMSSubCall(name, objects.Count + 1);
objects[name] = sc;
}
// generate the opcode and the parameters and memorize the types for later check
sc.StartCallerMemorization();
int numpar = tokens.Count - 2;
currentobject.AddOpCode(new byte[] { 0x09 }); // CALL
currentobject.AddConstant(sc.id); // ID of called subcall
currentobject.AddConstant(numpar);
for (int i = 0; i < numpar; i++)
{
Object p = DecodeAndAddParameter(locals, tokens[2 + i]);
sc.MemorizeCallerParameter(p); // keep for later type check
}
}
// process a label declaration
else if (first.EndsWith(":"))
{
if (first.IndexOf(':') < first.Length - 1)
{
throw new AssemblerException("Label must only have one trailing ':'");
}
currentobject.MemorizeLabel(first.Substring(0, first.Length - 1));
}
else
{
// process regular VMCommands
VMCommand c;
int paramstart = 0;
if (commands.ContainsKey(tokens[0]))
{
c = commands[tokens[0]];
paramstart = 1;
}
else if (tokens.Count < 2)
{
throw new AssemblerException("Unknown opcode " + tokens[0]);
}
else
{
String compound = tokens[0] + " " + tokens[1];
if (commands.ContainsKey(compound))
{
c = commands[compound];
paramstart = 2;
}
else
{
throw new AssemblerException("Unknown opcode " + compound);
}
}
int paramcount = c.parameters.Length; // this is the default parameter number (can be modifed by some special opcodes)
// create opcode and parameters
currentobject.AddOpCode(c.opcode);
for (int i = 0; i < paramcount; i++)
{
if (paramstart + i >= tokens.Count)
{
throw new AssemblerException("Too few parameters for " + c.name);
}
// of more paramerters then specified, repeat the last type (can only happen for opcodes with variable parameter number)
int pidx = Math.Min(i, c.parameters.Length - 1);
if (c.parameters[pidx] == DataType.Label) // special handling for jump label parameters
{
currentobject.AddLabelReference(tokens[paramstart + i]);
}
else if (c.parameters[pidx] == DataType.VMThread) // special handling for VM thread identifier
{
String name = tokens[paramstart + i];
LMSThread th = null;
// the name is already known
if (objects.ContainsKey(name))
{
LMSObject o = objects[name];
if (!(o is LMSThread))
{
throw new AssemblerException("Trying to start an object that is not defined as a thread");
}
th = (LMSThread)o;
}
// name is not known - create an empty thread object right here
else
{
th = new LMSThread(name, objects.Count + 1);
objects[name] = th;
}
currentobject.AddConstant(th.id);
}
else if (c.parameters[pidx] == DataType.VMSubcall) // special handling for VM subcall identifier
{
String name = tokens[paramstart + i];
if (name.Equals("0"))
{
// no subcall id - want to access something global
currentobject.AddConstant(0);
}
else
{
LMSSubCall th = null;
// the name is already known
if (objects.ContainsKey(name))
{
LMSObject o = objects[name];
if (!(o is LMSSubCall))
{
throw new AssemblerException("Trying to access an object that is not defined as a subcall");
}
th = (LMSSubCall)o;
}
// name is not known - create an empty thread object right here
else
{
th = new LMSSubCall(name, objects.Count + 1);
objects[name] = th;
}
currentobject.AddConstant(th.id);
}
}
else if (c.parameters[pidx] == DataType.ParameterCount) // special handling for opcodes with variable parameter number
{
Int32 p;
if (!Int32.TryParse(tokens[paramstart + i], NumberStyles.Integer, CultureInfo.InvariantCulture, out p))
{
throw new AssemblerException("Can not decode parameter count specifier");
}
if (p < 0 || p > 1000000000)
{
throw new AssemblerException("Parameter count specifier out of range");
}
currentobject.AddConstant(p);
paramcount = c.parameters.Length - 1 + p; // calculate number of parameters needed because of given specifier
}
else
{ // normal parameters (numbers, strings, variables)
Object a = DecodeAndAddParameter(locals, tokens[paramstart + i]);
DataTypeChecker.check(a, c.parameters[pidx], c.access[pidx]);
}
}
// check final number of parameters that were generated
if (paramstart + paramcount != tokens.Count)
{
throw new AssemblerException("Invalid number of parameters for " + c.name);
}
}
}
}
