Refactored floating point instruction handlers for better organization and maintainability. Split generic handlers into specialized classes for DD and DF opcodes.

X86Disassembler/X86/Handlers/FloatingPoint/Comparison/FcomppHandler.cs

@@ -0,0 +1,63 @@
+namespace X86Disassembler.X86.Handlers.FloatingPoint.Comparison;
+
+using X86Disassembler.X86.Operands;
+
+/// <summary>
+/// Handler for FCOMPP instruction (DE D9)
+/// </summary>
+public class FcomppHandler : InstructionHandler
+{
+    /// <summary>
+    /// Initializes a new instance of the FcomppHandler class
+    /// </summary>
+    /// <param name="decoder">The instruction decoder that owns this handler</param>
+    public FcomppHandler(InstructionDecoder decoder)
+        : base(decoder)
+    {
+    }
+
+    /// <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)
+    {
+        // FCOMPP is DE D9
+        if (opcode != 0xDE) return false;
+
+        if (!Decoder.CanReadByte())
+        {
+            return false;
+        }
+
+        // Check if the ModR/M byte is exactly D9 (reg = 3, rm = 1, mod = 3)
+        byte modRm = Decoder.PeakByte();
+        return modRm == 0xD9;
+    }
+    
+    /// <summary>
+    /// Decodes a FCOMPP 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)
+    {
+        if (!Decoder.CanReadByte())
+        {
+            return false;
+        }
+
+        // Read the ModR/M byte
+        var (mod, reg, rm, _) = ModRMDecoder.ReadModRM();
+        
+        // Set the instruction type
+        instruction.Type = InstructionType.Fcompp;
+
+        // FCOMPP has no operands
+        instruction.StructuredOperands = [];
+
+        return true;
+    }
+}