/// <summary>
/// Gets the assembled machine code for section of code
/// </summary>
/// <param name="code">The lines of code for this section</param>
/// <param name="labelDict">A dict of labels and their absolute compiled positions</param>
/// <param name="regexOpcodes">A list of RegexOpcodes where each RegexOpcode matches with each corresponding line of code</param>
/// <returns></returns>
private static byte[] GetCode(string[] code, Dictionary <string, ushort> labelDict, RegexOpcode[] regexOpcodes)
{
var output = new List <byte>();
for (int i = 0; i < code.Length; i++)
{
RegexOpcode op = regexOpcodes[i];
if (op.Prefix != null)
{
output.Add((byte)op.Prefix);
}
output.Add(op.Code);
if (op.BytesFollowing > 0)
{
Match m = op.Regex.Match(code[i]);
// Group 1 is the number, either n, -n, nn, -nn, h or hh or a label
int n;
if (!int.TryParse(m.Groups[1].Value, out n))
{
// Special case for JP opcode, as it can have a label to jump to
var first2Chars = op.Op.Substring(0, 2);
if (first2Chars == "JP" || first2Chars == "CA")
{
n = labelDict[m.Groups[1].Value];
}
else
{
throw new ApplicationException(string.Format("The value {0} cannot be parsed", m.Groups[1].Value));
}
}
if (op.BytesFollowing >= 1)
{
output.Add(n > 0 ? (byte)n : (byte)(sbyte)n);
}
int top = n >> 8;
if (op.BytesFollowing == 2)
{
output.Add(top > 0 ? (byte)top : (byte)(sbyte)top);
}
}
}
return(output.ToArray());
}
/// <summary>
/// Goes through each line of code - if it is a valid opcode, it assigns a RegexOpcode to it.
/// </summary>
/// <param name="code"></param>
/// <returns></returns>
private static RegexOpcode[] GetRegexOpcodes(string[] code)
{
var regexOpcodes = new RegexOpcode[code.Length];
for (int i = 0; i < code.Length; i++)
{
RegexOpcode op = Program.Opcodes.FirstOrDefault(opcode => opcode.Regex.IsMatch(code[i]));
if (op == null)
{
throw new ApplicationException(string.Format("Line {0} is incorrect: '{1}' does not exist, or a number in it is too big/small/malformed for the instruction.", i, code[i]));
}
regexOpcodes[i] = op;
}
return(regexOpcodes);
}