private void Sbb16Imm16(Reg16 reg)
{
registers.Set(reg,
(ushort)(registers.Get(reg) - BinaryHelper.Read16Bit(_memory, _ip + 1) -
(flagsRegister.HasFlag(Flags.Carry) ? 1 : 0)));
_ip += 3;
}
private void Mov16Imm16()
{
var imm16 = BinaryHelper.Read16Bit(_memory, _ip + 4);
ModRm((x, y) => imm16, RegisterType.reg16, false);
_ip += 2;
}
private void RetnImm16()
{
var bytes = BinaryHelper.Read16Bit(_memory, _ip + 1);
Retn();
registers.Set(Reg16.sp, (ushort)(registers.Get(Reg16.sp) + bytes));
}
private ushort getEffectiveAddressFromModRm(ushort modrm, int ip)
{
switch (modrm >> 6)
{
case 0x00:
if ((modrm & 7) == 0x6)
{
var imm16 = BinaryHelper.Read16Bit(memory, ip + 2);
IpShift = 4;
return(imm16);
}
else
{
IpShift = 2;
return(getEffectiveAddress(modrm));
}
case 0x01:
var displacement = memory[ip + 2];
IpShift = 3;
return((ushort)(getEffectiveAddress(modrm) + displacement));
case 0x02:
var disp16 = BinaryHelper.Read16Bit(memory, ip + 2);
;
IpShift = 4;
return((ushort)(getEffectiveAddress(modrm) + disp16));
default:
throw new InvalidOperationException();
}
}
private void Cmp16Imm16(Reg16 reg)
{
var regValue = registers.Get(reg);
var immValue = BinaryHelper.Read16Bit(_memory, _ip + 1);
flagsRegister.SetFlagsFromInputAndResult(regValue - immValue, regValue, immValue);
_ip += 3;
}
private int GetImm(int bytes)
{
if (bytes == 1)
{
return(_memory[_ip + 2]);
}
return(BinaryHelper.Read16Bit(_memory, _ip + 2));
}
private void Xor16Imm16(Reg16 reg)
{
registers.Set(reg, (ushort)(registers.Get(reg) ^ BinaryHelper.Read16Bit(_memory, _ip + 1)));
_ip += 3;
}
private ushort GetUInt16FromMemory(int address)
{
return(BinaryHelper.Read16Bit(_memory, address));
}