move handlers

X86Disassembler/X86/Handlers/Jump/ConditionalJumpHandler.cs

@@ -0,0 +1,77 @@
+namespace X86Disassembler.X86.Handlers.Jump;
+
+/// <summary>
+/// Handler for conditional jump instructions (0x70-0x7F)
+/// </summary>
+public class ConditionalJumpHandler : InstructionHandler
+{
+    // Mnemonics for conditional jumps
+    private static readonly string[] ConditionalJumpMnemonics = new string[]
+    {
+        "jo", "jno", "jb", "jnb", "jz", "jnz", "jbe", "jnbe",
+        "js", "jns", "jp", "jnp", "jl", "jnl", "jle", "jnle"
+    };
+    
+    /// <summary>
+    /// Initializes a new instance of the ConditionalJumpHandler 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 ConditionalJumpHandler(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)
+    {
+        // Conditional jumps are in the range 0x70-0x7F
+        return opcode >= 0x70 && opcode <= 0x7F;
+    }
+    
+    /// <summary>
+    /// Decodes a conditional jump 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)
+    {
+        // Get the mnemonic from the table
+        int index = opcode - 0x70;
+        instruction.Mnemonic = ConditionalJumpMnemonics[index];
+        
+        // Get the current position in the code buffer
+        int position = Decoder.GetPosition();
+        
+        if (position >= Length)
+        {
+            return false;
+        }
+        
+        // Read the relative offset
+        sbyte offset = (sbyte)CodeBuffer[position];
+        
+        // According to x86 architecture, the jump offset is relative to the instruction following the jump
+        // For a conditional jump, the instruction is 2 bytes: opcode (1 byte) + offset (1 byte)
+        
+        // Calculate the target address:
+        // 1. Start with the current position (where the offset byte is)
+        // 2. Add 1 to account for the size of the offset byte itself
+        // 3. Add the offset value
+        int targetAddress = position + 1 + offset;
+        
+        // Move the decoder position past the offset byte
+        Decoder.SetPosition(position + 1);
+        
+        // Set the operands to the calculated target address
+        instruction.Operands = $"0x{targetAddress:X8}";
+        
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Jump/JmpRel32Handler.cs

@@ -0,0 +1,59 @@
+namespace X86Disassembler.X86.Handlers.Jump;
+
+/// <summary>
+/// Handler for JMP rel32 instruction (0xE9)
+/// </summary>
+public class JmpRel32Handler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the JmpRel32Handler 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 JmpRel32Handler(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 == 0xE9;
+    }
+    
+    /// <summary>
+    /// Decodes a JMP rel32 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
+        instruction.Mnemonic = "jmp";
+        
+        int position = Decoder.GetPosition();
+        
+        if (position + 4 > Length)
+        {
+            return false;
+        }
+        
+        // Read the relative offset
+        int offset = BitConverter.ToInt32(CodeBuffer, position);
+        Decoder.SetPosition(position + 4);
+        
+        // Calculate the target address
+        uint targetAddress = (uint)(position + offset + 4);
+        
+        // Set the operands
+        instruction.Operands = $"0x{targetAddress:X8}";
+        
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Jump/JmpRel8Handler.cs

@@ -0,0 +1,59 @@
+namespace X86Disassembler.X86.Handlers.Jump;
+
+/// <summary>
+/// Handler for JMP rel8 instruction (0xEB)
+/// </summary>
+public class JmpRel8Handler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the JmpRel8Handler 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 JmpRel8Handler(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 == 0xEB;
+    }
+    
+    /// <summary>
+    /// Decodes a JMP rel8 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
+        instruction.Mnemonic = "jmp";
+        
+        int position = Decoder.GetPosition();
+        
+        if (position >= Length)
+        {
+            return false;
+        }
+        
+        // Read the relative offset
+        sbyte offset = (sbyte)CodeBuffer[position];
+        Decoder.SetPosition(position + 1);
+        
+        // Calculate the target address
+        uint targetAddress = (uint)(position + offset + 1);
+        
+        // Set the operands
+        instruction.Operands = $"0x{targetAddress:X8}";
+        
+        return true;
+    }
+}

X86Disassembler/X86/Handlers/Jump/TwoByteConditionalJumpHandler.cs

@@ -0,0 +1,88 @@
+namespace X86Disassembler.X86.Handlers.Jump;
+
+/// <summary>
+/// Handler for two-byte conditional jump instructions (0x0F 0x80-0x8F)
+/// </summary>
+public class TwoByteConditionalJumpHandler : InstructionHandler
+{
+    // Mnemonics for conditional jumps
+    private static readonly string[] ConditionalJumpMnemonics = new string[]
+    {
+        "jo", "jno", "jb", "jnb", "jz", "jnz", "jbe", "jnbe",
+        "js", "jns", "jp", "jnp", "jl", "jnl", "jle", "jnle"
+    };
+    
+    /// <summary>
+    /// Initializes a new instance of the TwoByteConditionalJumpHandler 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 TwoByteConditionalJumpHandler(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)
+    {
+        // Two-byte conditional jumps start with 0x0F
+        if (opcode == 0x0F)
+        {
+            int position = Decoder.GetPosition();
+            if (position < Length)
+            {
+                byte secondByte = CodeBuffer[position];
+                // Second byte must be in the range 0x80-0x8F
+                return secondByte >= 0x80 && secondByte <= 0x8F;
+            }
+        }
+        
+        return false;
+    }
+    
+    /// <summary>
+    /// Decodes a two-byte conditional jump 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 second byte of the opcode
+        byte secondByte = CodeBuffer[position++];
+        Decoder.SetPosition(position);
+        
+        // Get the mnemonic from the table
+        int index = secondByte - 0x80;
+        instruction.Mnemonic = ConditionalJumpMnemonics[index];
+        
+        if (position + 4 > Length)
+        {
+            return false;
+        }
+        
+        // Read the relative offset (32-bit)
+        int offset = BitConverter.ToInt32(CodeBuffer, position);
+        Decoder.SetPosition(position + 4);
+        
+        // Calculate the target address
+        uint targetAddress = (uint)(position + offset + 4);
+        
+        // Set the operands
+        instruction.Operands = $"0x{targetAddress:X8}";
+        
+        return true;
+    }
+}