public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction) { var value = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument2, instruction.Argument2Value, instruction.Argument2Displacement); 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, value); break; case OpCodeManager.ARG_BYTE_REGISTER: cpu.SetRegisterU8((Register)instruction.Argument1Value, (byte)value); 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)value); } else { cpu.WriteU16(address, value); } break; default: throw new NotImplementedException(); } }
public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction) { var segment = Register.DS; if (instruction.SegmentPrefix != Register.Invalid) { segment = instruction.SegmentPrefix; } var sourceAddress = InstructionHelper.SegmentToAddress(cpu.GetRegister(segment), cpu.GetRegister(Register.SI)); var destAddress = InstructionHelper.SegmentToAddress(cpu.GetRegister(Register.ES), cpu.GetRegister(Register.DI)); byte size; if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { var value = cpu.ReadU8(sourceAddress); cpu.WriteU8(destAddress, value); size = 1; } else { var value = cpu.ReadU16(sourceAddress); cpu.WriteU16(destAddress, value); size = 2; } if (!cpu.GetFlags().Has(FlagsRegister.Direction)) { cpu.IncRegister(Register.DI, size); cpu.IncRegister(Register.SI, size); } else { cpu.DecRegister(Register.DI, size); cpu.DecRegister(Register.SI, size); } }
public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction) { byte size; if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { cpu.WriteU8(InstructionHelper.SegmentToAddress(cpu.GetRegister(Register.ES), cpu.GetRegister(Register.DI)), (byte)(cpu.GetRegister(Register.AX) & 0xFF)); size = 1; } else { cpu.WriteU16(InstructionHelper.SegmentToAddress(cpu.GetRegister(Register.ES), cpu.GetRegister(Register.DI)), cpu.GetRegister(Register.AX)); size = 2; } if (!cpu.GetFlags().Has(FlagsRegister.Direction)) { cpu.IncRegister(Register.DI, size); } else { cpu.DecRegister(Register.DI, size); } }
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(); } }
public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction) { var value1 = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement); var value2 = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument2, instruction.Argument2Value, instruction.Argument2Displacement); if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { value1 &= 0xFF; value2 &= 0xFF; } int result; bool carry; switch (instruction.Type) { case OpCodeManager.InstructionType.Adc: result = value1 + value2 + (cpu.GetFlags().Has(FlagsRegister.Carry) ? 1 : 0); InstructionHelper.CalculateAddFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Add: result = value1 + value2; InstructionHelper.CalculateAddFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.And: case OpCodeManager.InstructionType.Test: result = value1 & value2; InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Compare: case OpCodeManager.InstructionType.Subtract: result = value1 - value2; InstructionHelper.CalculateSubFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Or: result = value1 | value2; InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Rcl: if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { const int mask = 0x1FF; var shift = (value2 & 0x1F) % 9; result = (byte)value1; if (cpu.Flags.Has(FlagsRegister.Carry)) { result |= 0x100; } result = (byte)(result << shift) | (byte)(result >> (-shift & mask)); if ((result & 0x100) != 0) { cpu.Flags |= FlagsRegister.Carry; } else { cpu.Flags &= ~FlagsRegister.Carry; } if (value2 == 1) { if (((result & 0x100) != 0) ^ ((result & 0x80) != 0)) { cpu.Flags |= FlagsRegister.Overflow; } else { cpu.Flags &= ~FlagsRegister.Overflow; } } } else { const int mask = 0x1FFFF; var shift = (value2 & 0x1F) % 17; result = value1; if (cpu.Flags.Has(FlagsRegister.Carry)) { result |= 0x10000; } result = (ushort)(result << shift) | (ushort)(result >> (-shift & mask)); if ((result & 0x10000) != 0) { cpu.Flags |= FlagsRegister.Carry; } else { cpu.Flags &= ~FlagsRegister.Carry; } if (value2 == 1) { if (((result & 0x10000) != 0) ^ ((result & 0x8000) != 0)) { cpu.Flags |= FlagsRegister.Overflow; } else { cpu.Flags &= ~FlagsRegister.Overflow; } } } InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Rcr: if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { const int mask = 0x1FF; var shift = (value2 & 0x1F) % 9; result = (byte)value1; if (cpu.Flags.Has(FlagsRegister.Carry)) { result |= 0x100; } if ((result & 0x1) != 0) { cpu.Flags |= FlagsRegister.Carry; } else { cpu.Flags &= ~FlagsRegister.Carry; } result = (byte)(result >> shift) | (byte)(result << (-shift & mask)); if (value2 == 1) { if (((result & 0x80) != 0) ^ ((result & 0x40) != 0)) { cpu.Flags |= FlagsRegister.Overflow; } else { cpu.Flags &= ~FlagsRegister.Overflow; } } } else { const int mask = 0x1FFFF; var shift = (value2 & 0x1F) % 17; result = value1; if (cpu.Flags.Has(FlagsRegister.Carry)) { result |= 0x10000; } if ((result & 0x1) != 0) { cpu.Flags |= FlagsRegister.Carry; } else { cpu.Flags &= ~FlagsRegister.Carry; } result = (ushort)(result >> shift) | (ushort)(result << (-shift & mask)); if (value2 == 1) { if (((result & 0x8000) != 0) ^ ((result & 0x4000) != 0)) { cpu.Flags |= FlagsRegister.Overflow; } else { cpu.Flags &= ~FlagsRegister.Overflow; } } } //cpu.CalculateBitwiseFlags(instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Rol: if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { const int mask = 0xFF; var shift = value2 & mask; result = (byte)(value1 << shift) | (byte)(value1 >> (-shift & mask)); } else { const int mask = 0xFFFF; var shift = value2 & mask; result = (ushort)(value1 << shift) | (ushort)(value1 >> (-shift & mask)); } InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Ror: if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { const int mask = 0xFF; var shift = value2 & mask; result = (byte)(value1 >> shift) | (byte)(value1 << (-shift & mask)); } else { const int mask = 0xFFFF; var shift = value2 & mask; result = (ushort)(value1 >> shift) | (ushort)(value1 << (-shift & mask)); } InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Sbb: result = value1 - (value2 + (cpu.GetFlags().Has(FlagsRegister.Carry) ? 1 : 0)); InstructionHelper.CalculateSubFlags(cpu, instruction.Flag, value1, value2, result); break; case OpCodeManager.InstructionType.Shl: bool overflow; result = value1 << (value2 & 0x1F); InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, (ushort)(value2 & 0x1F), result); if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { carry = (result & 0x100) != 0; overflow = (result & 0x80) != 0; } else { carry = (result & 0x10000) != 0; overflow = (result & 0x8000) != 0; } if (carry) { cpu.Flags |= FlagsRegister.Carry; } if ((value2 & 0x1F) == 1 && overflow ^ carry) { cpu.Flags |= FlagsRegister.Overflow; } break; case OpCodeManager.InstructionType.Sar: if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { carry = (((sbyte)value1 >> ((value2 & 0x1F) - 1)) & 1) != 0; result = (sbyte)value1 >> (value2 & 0x1F); } else { carry = (((short)value1 >> ((value2 & 0x1F) - 1)) & 1) != 0; result = (short)value1 >> (value2 & 0x1F); } InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, (ushort)(value2 & 0x1F), result); if (carry) { cpu.Flags |= FlagsRegister.Carry; } break; case OpCodeManager.InstructionType.Shr: carry = ((value1 >> ((value2 & 0x1F) - 1)) & 1) != 0; result = value1 >> (value2 & 0x1F); InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, (ushort)(value2 & 0x1F), result); if (carry) { cpu.Flags |= FlagsRegister.Carry; } if ((value2 & 0x1F) == 1) { if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8)) { if ((value1 & 0x80) != 0) { cpu.Flags |= FlagsRegister.Overflow; } } else { if ((value1 & 0x8000) != 0) { cpu.Flags |= FlagsRegister.Overflow; } } } break; case OpCodeManager.InstructionType.Xor: result = value1 ^ value2; InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result); break; default: throw new NotImplementedException(); } var truncResult = instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8) ? (byte)result : (ushort)result; if (instruction.Type != OpCodeManager.InstructionType.Compare && instruction.Type != OpCodeManager.InstructionType.Test) { 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, truncResult); break; case OpCodeManager.ARG_BYTE_REGISTER: cpu.SetRegisterU8((Register)instruction.Argument1Value, (byte)truncResult); 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)truncResult); } else { cpu.WriteU16(address, truncResult); } break; default: throw new NotImplementedException(); } } }