public RuntimeFunction(UserFunction function)
{
if (function == null)
{
throw new ArgumentNullException(nameof(function));
}
IP = function.IP;
Parameters = new Variable[function.NumParameters];
for (int i = 0; i < function.NumParameters; i++)
{
Parameters[i] = new Variable();
}
Variables = new Variable[function.NumVariables];
for (int i = 0; i < function.NumVariables; i++)
{
Variables[i] = new Variable();
}
ReturnValue = new Variable();
}
/// <summary>
/// Loads a precompiled program from disk.
/// </summary>
/// <remarks>
/// NOTE: We should employ some sort of checksum to verify bytecode integrity.
/// </remarks>
/// <param name="path"></param>
public void Load(string path)
{
int i, count;
Reset();
try
{
using BinaryReader reader = new(File.Open(path, FileMode.Open));
// Check signature
i = reader.ReadInt32();
if (i != FileSignature)
{
throw new Exception(InvalidFileFormat);
}
// Read reserved int
i = reader.ReadInt32();
if (i != 0)
{
throw new Exception(InvalidFileFormat);
}
// Read flags
FileFlag flags = (FileFlag)reader.ReadInt32();
// Read bytecodes
count = reader.ReadInt32();
ByteCodes = new int[count];
for (i = 0; i < count; i++)
{
ByteCodes[i] = reader.ReadInt32();
}
// Read functions
count = reader.ReadInt32();
List <Function> functions = new(count);
for (i = 0; i < count; i++)
{
string name = reader.ReadString();
FunctionType type = (FunctionType)reader.ReadInt32();
if (type == FunctionType.Internal)
{
// Temporarily set non-nullable action to null
// We will correct further down
var function = new InternalFunction(name, null !);
functions.Add(function);
}
else if (type == FunctionType.Intrinsic)
{
var function = new IntrinsicFunction(name);
functions.Add(function);
}
else // FunctionType.User
{
var function = new UserFunction(name, 0)
{
IP = reader.ReadInt32(),
NumVariables = reader.ReadInt32(),
NumParameters = reader.ReadInt32(),
};
functions.Add(function);
}
}
// Read global variables
count = reader.ReadInt32();
Variables = new Variable[count];
for (i = 0; i < count; i++)
{
Variables[i] = ReadVariable(reader);
}
// Read literals
count = reader.ReadInt32();
Literals = new Variable[count];
for (i = 0; i < count; i++)
{
Literals[i] = ReadVariable(reader);
}
// Read line numbers
if (flags.HasFlag(FileFlag.HasLineNumbers))
{
count = reader.ReadInt32();
LineNumbers = new int[count];
for (i = 0; i < count; i++)
{
LineNumbers[i] = reader.ReadInt32();
}
Debug.Assert(LineNumbers.Length == ByteCodes.Length);
}
// Fixup internal functions
foreach (var function in functions.OfType <InternalFunction>())
{
if (InternalFunctions.InternalFunctionLookup.TryGetValue(function.Name, out InternalFunctionInfo? info))
{
function.Action = info.Action;
function.MinParameters = info.MinParameters;
function.MaxParameters = info.MaxParameters;
}
else
{
throw new Exception($"Internal intrinsic function \"{function.Name}\" not found");
}
}
Functions = functions.ToArray();
}
catch (Exception)
{
// Clear to known state if error
Reset();
throw;
}
}