public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
{
var value = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
int result;
switch (instruction.Type)
{
case OpCodeManager.InstructionType.Decrement:
result = value - 1;
InstructionHelper.CalculateDecFlags(cpu, instruction.Flag, value, 1, result);
break;
case OpCodeManager.InstructionType.Increment:
result = value + 1;
InstructionHelper.CalculateIncFlags(cpu, instruction.Flag, value, 1, result);
break;
case OpCodeManager.InstructionType.Negate:
result = ~value + 1;
InstructionHelper.CalculateSubFlags(cpu, instruction.Flag, 0, value, result);
break;
case OpCodeManager.InstructionType.Not:
result = ~value;
break;
default:
throw new OutOfMemoryException();
}
switch (instruction.Argument1)
{
case (int)Register.AX:
case (int)Register.CX:
case (int)Register.DX:
case (int)Register.BX:
case (int)Register.SP:
case (int)Register.BP:
case (int)Register.SI:
case (int)Register.DI:
case (int)Register.IP:
case (int)Register.CS:
case (int)Register.DS:
case (int)Register.ES:
case (int)Register.SS:
cpu.SetRegister((Register)instruction.Argument1, (ushort)result);
break;
case OpCodeManager.ARG_BYTE_REGISTER:
cpu.SetRegisterU8((Register)instruction.Argument1Value, (byte)result);
break;
case OpCodeManager.ARG_DEREFERENCE:
case OpCodeManager.ARG_MEMORY:
var address = InstructionHelper.GetInstructionRealAddress(cpu, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
{
cpu.WriteU8(address, (byte)result);
}
else
{
cpu.WriteU16(address, (ushort)result);
}
break;
default:
throw new NotImplementedException();
}
}
