public void Load(Computer computer, Program program)
{
// skip entry point stuff
// Load the code segment into memory.
for (int i = 0; i < program.codeSegment.Item1.Count; i++)
{
// stack (grows downwards to data/code).
computer.memory.virtualAddressSpace[i].value = program.codeSegment.Item1[i];
computer.memory.virtualAddressSpace[i].asmLine = program.codeSegment.Item2[i];
}
int nextLoadPoint = program.codeSegment.Item1.Count; // 8-byte stack reservation.
// Load the data segment into memory.
//todo - doesn't work at mo, because it needs to minus the nextLoadPoint, not add it, perhaps, in memory?
/*for (int i = 0; i < program.dataSegment.Count; i++)
{
computer.memory.virtualAddressSpace[i + nextLoadPoint].value = program.dataSegment[i];
}*/
nextLoadPoint += program.dataSegment.Count;
// Set IP (instruction pointer) to entry point.
computer.cPU.GetRegisters().SetRegister((int)(X86Registers.RegisterPointers.INSTRUCTION_POINTER), 0, Helper.GetHelper().PadWithBytes((byte)(program.entryPoint), 4));
}
public X86InstructionSet(Computer parentComputer)
{
this.parentComputer = parentComputer;
// * Opcodes. *
this.opcodes = new Dictionary<string, string>();
this.opcodes.Add("_184", "MOV EAX, ");
this.opcodes.Add("_232", "CALL ");
this.opcodes.Add("_40", "INC EAX");
this.opcodes.Add("_50", "PUSH EAX");
this.opcodes.Add("_58", "POP EAX");
this.opcodes.Add("_195", "RET");
this.opcodes.Add("_106", "PUSH ");
this.opcodes.Add("_233", "JMP ");
this.opcodes.Add("_89", "MOV ");
}
public void ExecuteOpcode(Computer computer, byte opcode)
{
// Do your reflective invocation thing here...
Type reflectionType = typeof(X86InstructionSet);
// Turn 32-bit instruction opcode into instruction opcode.
// Prep for 'reflective invoke' :-).
int line = computer.cPU.GetRegisters().GetRegister((int)(X86Registers.RegisterPointers.INSTRUCTION_POINTER), 0)[0];
string methodName = "_" + computer.memory.virtualAddressSpace[line].value;//Encoding.ASCII.GetString(this.operands[0].value).Trim(new char[] { '\0' }); // Remove empty character bytes from opcode.
MethodInfo info = reflectionType.GetMethod(methodName);
ParameterInfo[] parameterInfos = info.GetParameters();
if (parameterInfos.Length > 0)
{
byte[] parameters = new byte[0];
Array.Resize(ref parameters, parameters.Count() + 1);
parameters[parameters.Count() - 1] = computer.memory.virtualAddressSpace[line + 1].value; // Next byte is opcode's needed parameter.
IInstructionSet instructions = new X86InstructionSet(computer); // todo <-- horrible hack creating a new instruction set on the fly, here... //computer.cPU.instructionSet;
info.Invoke(instructions, new object[] { parameters }); // Turn byte array into object array with single byte array element.
}
else
{
IInstructionSet instructions = new X86InstructionSet(computer); // todo horrible hack creating a new instruction set on the fly, here... //computer.cPU.instructionSet;
info.Invoke(instructions, null); // Turn byte array into object array with single byte array element.
}
}
public Program CreateProgram(Computer computer, List<string> listing)
{
// Fingers on the Spectrum cassette player...
// 1. Execute interpreter on listing.
Interpreter interpreter = new Interpreter();
return interpreter.Interpret(listing);
}
//public int line { get; set; }
public void Step(Computer computer)
{
// Run the program.
//for (i = 0; i < computer.memory.virtualAddressSpace.Count; i++)
//{
//ExecuteOpcode(computer, computer.memory.virtualAddressSpace[line]);
int castedIP = computer.cPU.GetRegisters().GetRegister((int)(X86Registers.RegisterPointers.INSTRUCTION_POINTER), 0)[0];
ExecuteOpcode(computer, computer.memory.virtualAddressSpace[castedIP].value);
//this.line += ToSkip(computer.memory.virtualAddressSpace[castedIP]); // Get next opcode to instruction ready to read.
// todo - Horrible hack to re-get the IP if it may have been changed by an instruction such as RET.
castedIP = computer.cPU.GetRegisters().GetRegister((int)(X86Registers.RegisterPointers.INSTRUCTION_POINTER), 0)[0];
X86InstructionSet instructions = new X86InstructionSet(computer); // todo Remove, as only instantiated for the ToSkip() call below.
int toSkip = instructions.ToSkip(computer.memory.virtualAddressSpace[castedIP].value);
int toSkip2 = toSkip + computer.cPU.GetRegisters().GetRegister((int)(X86Registers.RegisterPointers.INSTRUCTION_POINTER), 0)[0];
computer.cPU.GetRegisters().SetRegister((int)(X86Registers.RegisterPointers.INSTRUCTION_POINTER), 0, Helper.GetHelper().PadWithBytes((byte)(toSkip2), 4)); // Get next opcode to instruction ready to read.
}
// * Constructor *
public X86CPU(Computer computer)
{
this.x86InstructionSet = new X86InstructionSet(computer);
this.x86Registers = new X86Registers();
}
public void PrepareProgram(Computer computer, Program program)
{
// 2. Execute loader on source.
loader.Load(computer, program);
}
