Added complete set of OR instruction handlers with tests

X86Disassembler/X86/Handlers/InstructionHandlerFactory.cs

@@ -206,6 +206,11 @@ public class InstructionHandlerFactory
     {
         // Add Or handlers
         _handlers.Add(new OrR8Rm8Handler(_codeBuffer, _decoder, _length));
+        _handlers.Add(new OrR32Rm32Handler(_codeBuffer, _decoder, _length));
+        _handlers.Add(new OrAlImmHandler(_codeBuffer, _decoder, _length));
+        _handlers.Add(new OrEaxImmHandler(_codeBuffer, _decoder, _length));
+        _handlers.Add(new OrImmWithRm32Handler(_codeBuffer, _decoder, _length));
+        _handlers.Add(new OrImmWithRm32SignExtendedHandler(_codeBuffer, _decoder, _length));
     }
     
     /// <summary>

X86Disassembler/X86/Handlers/Or/OrAlImmHandler.cs

@@ -0,0 +1,56 @@
+namespace X86Disassembler.X86.Handlers.Or;
+
+/// <summary>
+/// Handler for OR AL, imm8 instruction (0x0C)
+/// </summary>
+public class OrAlImmHandler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the OrAlImmHandler 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 OrAlImmHandler(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)
+    {
+        return opcode == 0x0C;
+    }
+
+    /// <summary>
+    /// Decodes an OR AL, imm8 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)
+    {
+        int position = Decoder.GetPosition();
+
+        if (position >= Length)
+        {
+            return false;
+        }
+
+        // Read the immediate byte
+        byte imm8 = CodeBuffer[position++];
+        Decoder.SetPosition(position);
+
+        // Set the mnemonic
+        instruction.Mnemonic = "or";
+
+        // Set the operands
+        instruction.Operands = $"al, 0x{imm8:X2}";
+
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Or/OrEaxImmHandler.cs

@@ -0,0 +1,60 @@
+namespace X86Disassembler.X86.Handlers.Or;
+
+/// <summary>
+/// Handler for OR EAX, imm32 instruction (0x0D)
+/// </summary>
+public class OrEaxImmHandler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the OrEaxImmHandler 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 OrEaxImmHandler(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)
+    {
+        return opcode == 0x0D;
+    }
+
+    /// <summary>
+    /// Decodes an OR EAX, imm32 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)
+    {
+        int position = Decoder.GetPosition();
+
+        if (position + 3 >= Length)
+        {
+            return false;
+        }
+
+        // Read the immediate dword (little-endian)
+        byte b0 = CodeBuffer[position++];
+        byte b1 = CodeBuffer[position++];
+        byte b2 = CodeBuffer[position++];
+        byte b3 = CodeBuffer[position++];
+        uint imm32 = (uint)(b0 | (b1 << 8) | (b2 << 16) | (b3 << 24));
+        Decoder.SetPosition(position);
+
+        // Set the mnemonic
+        instruction.Mnemonic = "or";
+
+        // Set the operands
+        instruction.Operands = $"eax, 0x{imm32:X8}";
+
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Or/OrImmWithRm32Handler.cs

@@ -0,0 +1,115 @@
+namespace X86Disassembler.X86.Handlers.Or;
+
+/// <summary>
+/// Handler for OR r/m32, imm32 instruction (0x81 /1)
+/// </summary>
+public class OrImmWithRm32Handler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the OrImmWithRm32Handler 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 OrImmWithRm32Handler(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)
+    {
+        return opcode == 0x81;
+    }
+
+    /// <summary>
+    /// Decodes an OR r/m32, imm32 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)
+    {
+        int position = Decoder.GetPosition();
+
+        if (position >= Length)
+        {
+            return false;
+        }
+
+        // Read the ModR/M byte
+        byte modRM = CodeBuffer[position++];
+        
+        // Extract the fields from the ModR/M byte
+        byte mod = (byte)((modRM & 0xC0) >> 6);
+        byte reg = (byte)((modRM & 0x38) >> 3);
+        byte rm = (byte)(modRM & 0x07);
+        
+        // Check if this is an OR instruction (reg field = 1)
+        if (reg != 1)
+        {
+            return false;
+        }
+        
+        // Process SIB and displacement bytes if needed
+        if (mod != 3 && rm == 4) // SIB byte present
+        {
+            if (position >= Length)
+            {
+                return false;
+            }
+            position++; // Skip SIB byte
+        }
+        
+        // Handle displacement
+        if ((mod == 1 && position >= Length) || (mod == 2 && position + 3 >= Length))
+        {
+            return false;
+        }
+        
+        if (mod == 1) // 8-bit displacement
+        {
+            position++;
+        }
+        else if (mod == 2) // 32-bit displacement
+        {
+            position += 4;
+        }
+        
+        // Read the immediate dword
+        if (position + 3 >= Length)
+        {
+            return false;
+        }
+        
+        byte b0 = CodeBuffer[position++];
+        byte b1 = CodeBuffer[position++];
+        byte b2 = CodeBuffer[position++];
+        byte b3 = CodeBuffer[position++];
+        uint imm32 = (uint)(b0 | (b1 << 8) | (b2 << 16) | (b3 << 24));
+        Decoder.SetPosition(position);
+
+        // Set the mnemonic
+        instruction.Mnemonic = "or";
+
+        // Get the operand string
+        string operand;
+        if (mod != 3) // Memory operand
+        {
+            operand = ModRMDecoder.DecodeModRM(mod, rm, false);
+        }
+        else // Register operand
+        {
+            operand = GetRegister32(rm);
+        }
+
+        // Set the operands
+        instruction.Operands = $"{operand}, 0x{imm32:X8}";
+
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Or/OrImmWithRm32SignExtendedHandler.cs

@@ -0,0 +1,111 @@
+namespace X86Disassembler.X86.Handlers.Or;
+
+/// <summary>
+/// Handler for OR r/m32, imm8 sign-extended instruction (0x83 /1)
+/// </summary>
+public class OrImmWithRm32SignExtendedHandler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the OrImmWithRm32SignExtendedHandler 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 OrImmWithRm32SignExtendedHandler(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)
+    {
+        return opcode == 0x83;
+    }
+
+    /// <summary>
+    /// Decodes an OR r/m32, imm8 sign-extended 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)
+    {
+        int position = Decoder.GetPosition();
+
+        if (position >= Length)
+        {
+            return false;
+        }
+
+        // Read the ModR/M byte
+        byte modRM = CodeBuffer[position++];
+        
+        // Extract the fields from the ModR/M byte
+        byte mod = (byte)((modRM & 0xC0) >> 6);
+        byte reg = (byte)((modRM & 0x38) >> 3);
+        byte rm = (byte)(modRM & 0x07);
+        
+        // Check if this is an OR instruction (reg field = 1)
+        if (reg != 1)
+        {
+            return false;
+        }
+        
+        // Process SIB and displacement bytes if needed
+        if (mod != 3 && rm == 4) // SIB byte present
+        {
+            if (position >= Length)
+            {
+                return false;
+            }
+            position++; // Skip SIB byte
+        }
+        
+        // Handle displacement
+        if ((mod == 1 && position >= Length) || (mod == 2 && position + 3 >= Length))
+        {
+            return false;
+        }
+        
+        if (mod == 1) // 8-bit displacement
+        {
+            position++;
+        }
+        else if (mod == 2) // 32-bit displacement
+        {
+            position += 4;
+        }
+        
+        // Read the immediate byte
+        if (position >= Length)
+        {
+            return false;
+        }
+        
+        byte imm8 = CodeBuffer[position++];
+        Decoder.SetPosition(position);
+
+        // Set the mnemonic
+        instruction.Mnemonic = "or";
+
+        // Get the operand string
+        string operand;
+        if (mod != 3) // Memory operand
+        {
+            operand = ModRMDecoder.DecodeModRM(mod, rm, false);
+        }
+        else // Register operand
+        {
+            operand = GetRegister32(rm);
+        }
+
+        // Set the operands
+        instruction.Operands = $"{operand}, {imm8}";
+
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Or/OrR32Rm32Handler.cs

@@ -0,0 +1,73 @@
+namespace X86Disassembler.X86.Handlers.Or;
+
+/// <summary>
+/// Handler for OR r32, r/m32 instruction (0x0B)
+/// </summary>
+public class OrR32Rm32Handler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the OrR32Rm32Handler 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 OrR32Rm32Handler(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)
+    {
+        return opcode == 0x0B;
+    }
+
+    /// <summary>
+    /// Decodes an OR r32, r/m32 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)
+    {
+        int position = Decoder.GetPosition();
+
+        if (position >= Length)
+        {
+            return false;
+        }
+
+        // Read the ModR/M byte
+        byte modRM = CodeBuffer[position++];
+        Decoder.SetPosition(position);
+
+        // Extract the fields from the ModR/M byte
+        byte mod = (byte)((modRM & 0xC0) >> 6);
+        byte reg = (byte)((modRM & 0x38) >> 3);
+        byte rm = (byte)(modRM & 0x07);
+
+        // Set the mnemonic
+        instruction.Mnemonic = "or";
+
+        // Get the register name
+        string regName = GetRegister32(reg);
+
+        // For memory operands, set the operand
+        if (mod != 3) // Memory operand
+        {
+            string operand = ModRMDecoder.DecodeModRM(mod, rm, false);
+            instruction.Operands = $"{regName}, {operand}";
+        }
+        else // Register operand
+        {
+            string rmName = GetRegister32(rm);
+            instruction.Operands = $"{regName}, {rmName}";
+        }
+
+        return true;
+    }
+}

X86DisassemblerTests/OrInstructionTests.cs

@@ -46,4 +46,118 @@ public class OrInstructionTests
         Assert.Equal("or", instructions[0].Mnemonic);
         Assert.Equal("al, byte ptr [eax]", instructions[0].Operands);
     }
+    
+    /// <summary>
+    /// Tests the OR r32, r/m32 instruction (0x0B)
+    /// </summary>
+    [Fact]
+    public void TestOrR32Rm32()
+    {
+        // Arrange
+        byte[] code = { 0x0B, 0xC8 }; // OR ECX, EAX
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("or", instructions[0].Mnemonic);
+        Assert.Equal("ecx, eax", instructions[0].Operands);
+    }
+    
+    /// <summary>
+    /// Tests the OR r32, m32 instruction (0x0B) with memory operand
+    /// </summary>
+    [Fact]
+    public void TestOrR32M32()
+    {
+        // Arrange
+        byte[] code = { 0x0B, 0x00 }; // OR EAX, DWORD PTR [EAX]
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("or", instructions[0].Mnemonic);
+        Assert.Equal("eax, dword ptr [eax]", instructions[0].Operands);
+    }
+    
+    /// <summary>
+    /// Tests the OR AL, imm8 instruction (0x0C)
+    /// </summary>
+    [Fact]
+    public void TestOrAlImm8()
+    {
+        // Arrange
+        byte[] code = { 0x0C, 0x42 }; // OR AL, 0x42
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("or", instructions[0].Mnemonic);
+        Assert.Equal("al, 0x42", instructions[0].Operands);
+    }
+    
+    /// <summary>
+    /// Tests the OR EAX, imm32 instruction (0x0D)
+    /// </summary>
+    [Fact]
+    public void TestOrEaxImm32()
+    {
+        // Arrange
+        byte[] code = { 0x0D, 0x78, 0x56, 0x34, 0x12 }; // OR EAX, 0x12345678
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("or", instructions[0].Mnemonic);
+        Assert.Equal("eax, 0x12345678", instructions[0].Operands);
+    }
+    
+    /// <summary>
+    /// Tests the OR r/m32, imm32 instruction (0x81 /1)
+    /// </summary>
+    [Fact]
+    public void TestOrRm32Imm32()
+    {
+        // Arrange
+        byte[] code = { 0x81, 0xC8, 0x78, 0x56, 0x34, 0x12 }; // OR EAX, 0x12345678
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("or", instructions[0].Mnemonic);
+        Assert.Equal("eax, 0x12345678", instructions[0].Operands);
+    }
+    
+    /// <summary>
+    /// Tests the OR r/m32, imm8 sign-extended instruction (0x83 /1)
+    /// </summary>
+    [Fact]
+    public void TestOrRm32Imm8SignExtended()
+    {
+        // Arrange
+        byte[] code = { 0x83, 0xC8, 0x42 }; // OR EAX, 0x42
+        
+        // Act
+        Disassembler disassembler = new Disassembler(code, 0x1000);
+        var instructions = disassembler.Disassemble();
+        
+        // Assert
+        Assert.Single(instructions);
+        Assert.Equal("or", instructions[0].Mnemonic);
+        Assert.Equal("eax, 0x00000042", instructions[0].Operands);
+    }
 }