Add support for XOR instruction

X86Disassembler/X86/Handlers/ArithmeticHandler.cs

@@ -0,0 +1,126 @@
+namespace X86Disassembler.X86.Handlers;
+
+/// <summary>
+/// Handler for arithmetic and logical instructions (ADD, SUB, AND, OR, XOR, etc.)
+/// </summary>
+public class ArithmeticHandler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the ArithmeticHandler class
+    /// </summary>
+    /// <param name="codeBuffer">The buffer containing the code to decode</param>
+    /// <param name="decoder">The instruction decoder that owns this handler</param>
+    /// <param name="length">The length of the buffer</param>
+    public ArithmeticHandler(byte[] codeBuffer, InstructionDecoder decoder, int length) 
+        : base(codeBuffer, decoder, length)
+    {
+    }
+    
+    /// <summary>
+    /// Checks if this handler can decode the given opcode
+    /// </summary>
+    /// <param name="opcode">The opcode to check</param>
+    /// <returns>True if this handler can decode the opcode</returns>
+    public override bool CanHandle(byte opcode)
+    {
+        // XOR instructions
+        if (opcode >= 0x30 && opcode <= 0x35)
+        {
+            return true;
+        }
+        
+        return false;
+    }
+    
+    /// <summary>
+    /// Decodes an arithmetic or logical instruction
+    /// </summary>
+    /// <param name="opcode">The opcode of the instruction</param>
+    /// <param name="instruction">The instruction object to populate</param>
+    /// <returns>True if the instruction was successfully decoded</returns>
+    public override bool Decode(byte opcode, Instruction instruction)
+    {
+        // Set the mnemonic based on the opcode
+        instruction.Mnemonic = OpcodeMap.GetMnemonic(opcode);
+        
+        int position = Decoder.GetPosition();
+        
+        if (position >= Length)
+        {
+            return false;
+        }
+        
+        switch (opcode)
+        {
+            case 0x30: // XOR r/m8, r8
+            case 0x31: // XOR r/m32, r32
+                {
+                    // Read the ModR/M byte
+                    var (mod, reg, rm, destOperand) = ModRMDecoder.ReadModRM();
+                    
+                    // Determine the source register
+                    string sourceReg;
+                    if (opcode == 0x30) // 8-bit registers
+                    {
+                        sourceReg = ModRMDecoder.GetRegister8(reg);
+                    }
+                    else // 32-bit registers
+                    {
+                        sourceReg = ModRMDecoder.GetRegister32(reg);
+                    }
+                    
+                    // Set the operands
+                    instruction.Operands = $"{destOperand}, {sourceReg}";
+                    return true;
+                }
+                
+            case 0x32: // XOR r8, r/m8
+            case 0x33: // XOR r32, r/m32
+                {
+                    // Read the ModR/M byte
+                    var (mod, reg, rm, srcOperand) = ModRMDecoder.ReadModRM();
+                    
+                    // Determine the destination register
+                    string destReg;
+                    if (opcode == 0x32) // 8-bit registers
+                    {
+                        destReg = ModRMDecoder.GetRegister8(reg);
+                    }
+                    else // 32-bit registers
+                    {
+                        destReg = ModRMDecoder.GetRegister32(reg);
+                    }
+                    
+                    // Set the operands
+                    instruction.Operands = $"{destReg}, {srcOperand}";
+                    return true;
+                }
+                
+            case 0x34: // XOR AL, imm8
+                {
+                    if (position < Length)
+                    {
+                        byte imm8 = CodeBuffer[position];
+                        Decoder.SetPosition(position + 1);
+                        instruction.Operands = $"al, 0x{imm8:X2}";
+                        return true;
+                    }
+                    break;
+                }
+                
+            case 0x35: // XOR EAX, imm32
+                {
+                    if (position + 3 < Length)
+                    {
+                        uint imm32 = BitConverter.ToUInt32(CodeBuffer, position);
+                        Decoder.SetPosition(position + 4);
+                        instruction.Operands = $"eax, 0x{imm32:X8}";
+                        return true;
+                    }
+                    break;
+                }
+        }
+        
+        return false;
+    }
+}

X86Disassembler/X86/InstructionDecoder.cs

@@ -50,7 +50,8 @@ public class InstructionDecoder
             new DataTransferHandler(_codeBuffer, this, _length),
             new ControlFlowHandler(_codeBuffer, this, _length),
             new Group3Handler(_codeBuffer, this, _length),
-            new TestHandler(_codeBuffer, this, _length)
+            new TestHandler(_codeBuffer, this, _length),
+            new ArithmeticHandler(_codeBuffer, this, _length)
         };
     }
     

X86Disassembler/X86/OpcodeMap.cs

@@ -118,6 +118,14 @@ public class OpcodeMap
         OneByteOpcodes[0x6A] = "push"; // PUSH imm8
         OneByteOpcodes[0xCD] = "int";  // INT imm8
         OneByteOpcodes[0xE3] = "jecxz"; // JECXZ rel8
+        
+        // XOR instructions
+        OneByteOpcodes[0x30] = "xor"; // XOR r/m8, r8
+        OneByteOpcodes[0x31] = "xor"; // XOR r/m32, r32
+        OneByteOpcodes[0x32] = "xor"; // XOR r8, r/m8
+        OneByteOpcodes[0x33] = "xor"; // XOR r32, r/m32
+        OneByteOpcodes[0x34] = "xor"; // XOR AL, imm8
+        OneByteOpcodes[0x35] = "xor"; // XOR EAX, imm32
     }
     
     /// <summary>