public static VMRoutine Assemble(VM vm, BHAV bhav)
{
var context = vm.Context;
var routine = new VMRoutine();
routine.Locals = bhav.Locals;
routine.Arguments = bhav.Args;
routine.Type = bhav.Type;
routine.VM = vm;
routine.Rti = new VMFunctionRTI {
Name = bhav.ChunkLabel
};
VMInstruction[] instructions = new VMInstruction[bhav.Instructions.Length];
for (var i = 0; i < bhav.Instructions.Length; i++)
{
var bhavInstruction = bhav.Instructions[i];
var instruction = new VMInstruction();
instruction.Index = (byte)i;
instruction.Opcode = bhavInstruction.Opcode;
instruction.Operand = bhavInstruction.Operand;
instruction.FalsePointer = bhavInstruction.FalsePointer;
instruction.TruePointer = bhavInstruction.TruePointer;
instruction.Function = routine;
/** Routine call **/
if (instruction.Opcode >= 256)
{
var operand = new VMSubRoutineOperand();
operand.Read(bhavInstruction.Operand);
instruction.Operand = operand;
}
else
{
var primitive = context.GetPrimitive(instruction.Opcode);
if (primitive != null)
{
if (primitive.OperandModel != null)
{
VMPrimitiveOperand operand = (VMPrimitiveOperand)Activator.CreateInstance(primitive.OperandModel);
operand.Read(bhavInstruction.Operand);
instruction.Operand = operand;
}
}
}
instructions[i] = instruction;
}
routine.Instructions = instructions;
return routine;
}
private void ExecuteSubRoutine(VMStackFrame frame, BHAV bhav, GameIffResource codeOwner, VMSubRoutineOperand args)
{
if (bhav == null){
Pop(VMPrimitiveExitCode.ERROR);
return;
}
System.Diagnostics.Debug.WriteLine("Invoke: " + bhav.ChunkLabel);
System.Diagnostics.Debug.WriteLine("");
var routine = frame.VM.Assemble(bhav);
var childFrame = new VMStackFrame
{
Routine = routine,
Caller = frame.Caller,
Callee = frame.Callee,
CodeOwner = codeOwner,
StackObject = frame.StackObject
};
childFrame.Args = new short[routine.Arguments];
for (var i = 0; i < childFrame.Args.Length; i++){
var argValue = args.Arguments[i];
if (argValue == -1)
{
/** TODO: Is this the right rule? Maybe a flag decides when to copy from temp? **/
argValue = TempRegisters[i];
}
childFrame.Args[i] = argValue;
}
Push(childFrame);
}