private string ParseStack(FileStream inS)
{
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("Push " + ParseNum(inS).ToString());
case 1:
throw new Exception("Parse Stack Manipultion encountered an invalid operand! [Tab]");
case 2:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("Copy");
case 1:
return("Swap");
case 2:
return("Pop");
}
throw new Exception("Parse Stack Manipulation followed by [LF] encountered an unknown operand!");
}
throw new Exception("Parse Stack Manipulation encountered an unknown operand!");
}
private string ParseFlow(FileStream inS)
{
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("Label " + ParseNum(inS).ToString());
case 1:
return("Call " + ParseNum(inS).ToString());
case 2:
return("Jump " + ParseNum(inS).ToString());
}
throw new Exception("Parse Flow followed by [Space] encountered an unknown operand!");
case 1:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("Jz " + ParseNum(inS).ToString());
case 1:
return("Jn " + ParseNum(inS).ToString());
case 2:
return("Ret");
}
throw new Exception("Parse Flow followed by [Tab] encountered an unknown operand!");
case 2:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
throw new Exception("Parse Flow followed by [LF] encountered an invalid operand! [Space]");
case 1:
throw new Exception("Parse Flow followed by [LF] encountered an invalid operand! [Tab]");
case 2:
done = true;
return("End");
}
throw new Exception("Parse Flow followed by [LF] encountered an unknown operand!");
}
throw new Exception("Parse Flow encountered an unknown operand!");
}
private string ParseHeap(FileStream inS)
{
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("St");
case 1:
return("Ld");
case 2:
throw new Exception("Parse Heap encountered an invalid operand! [LF]");
}
throw new Exception("Parse Heap encountered an unknown operand!");
}
public void ParseInstruction(int n, FileStream inS)
{
if (done)
{
throw new Exception("Instructions continue after end of program reached!");
}
switch (n)
{
// stack manip
case 0:
insts.Add(ParseStack(inS));
break;
// arithmetic, heap, or I/O
case 1:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
insts.Add(ParseArithmetic(inS));
break;
case 1:
insts.Add(ParseHeap(inS));
break;
case 2:
insts.Add(ParseIO(inS));
break;
}
break;
// flow control
case 2:
insts.Add(ParseFlow(inS));
break;
}
if (WhitespaceAssembler.debug)
{
Console.WriteLine("Finished Instruction: " + insts[insts.Count - 1]);
}
}
private int ParseNum(FileStream inS)
{
bool done = false;
int signCheck = WhitespaceAssembler.GetNextChar(inS);
if (signCheck == 2)
{
throw new Exception("Parse Number encountered an invalid sign! [LF]");
}
bool positive = signCheck == 0;
int res = 0;
int bitCount = 0;
while (!done)
{
bitCount++;
if (bitCount > 31)
{
throw new Exception("Parse Number encountered a number larger than 31 bits!");
}
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
res <<= 1;
break;
case 1:
res <<= 1;
res += 1;
break;
case 2:
done = true;
break;
}
}
return(positive ? res : -res);
}
private string ParseIO(FileStream inS)
{
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("OutC");
case 1:
return("OutN");
case 2:
throw new Exception("Parse IO followed by [Space] encountered an invalid operand! [LF]");
}
throw new Exception("Parse IO followed by [Space] encountered an unknown operand!");
case 1:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("ReadC");
case 1:
return("ReadN");
case 2:
throw new Exception("Parse IO followed by [Tab] encountered an invalid operand! [LF]");
}
throw new Exception("Parse IO followed by [Tab] encountered an unknown operand!");
case 2:
throw new Exception("Parse IO encountered an invalid operand! [LF]");
}
throw new Exception("Parse IO encountered an unknown operand!");
}
private string ParseArithmetic(FileStream inS)
{
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("Add");
case 1:
return("Sub");
case 2:
return("Mult");
}
throw new Exception("Parse Arithmetic followed by [Space] encountered an unknown operand!");
case 1:
switch (WhitespaceAssembler.GetNextChar(inS))
{
case 0:
return("Div");
case 1:
return("Mod");
case 2:
throw new Exception("Parse Arithmetic followed by [Tab] encountered an invalid operand! [LF]");
}
throw new Exception("Parse Arithmetic followed by [Tab] encountered an unknown operand!");
case 2:
throw new Exception("Parse Arithmetic encountered an invalid operand! [LF]");
}
throw new Exception("Parse Arithmetic encountered an unknown operand!");
}