AsmResolver.X86.X86Disassembler.GetRegOrMemOperand32 C# (CSharp) Метод

        private X86Operand GetRegOrMemOperand32(byte registerToken, X86OperandSize size)
        {
            // Mechanism:
            // http://ref.x86asm.net/coder32.html#modrm_byte_32

            // ModR/M byte:
            //  mod | reg/mem | (reg2)
            // -----+---------+-------
            //  7 6 |  5 4 3  | (2 1 0)

            var modifier = (X86RegOrMemModifier)(registerToken >> 6);
            var operand = new X86Operand();

            // Register-only operands:
            if (modifier == X86RegOrMemModifier.RegisterOnly)
            {
                operand.Value = GetRegisterFromToken((byte)(registerToken & 0x7), GetRegisterSize(size));
                operand.OperandUsage = X86OperandUsage.Normal;
                return operand;
            }

            // Register-pointer operands are always 32-bit registers.
            var register = GetRegisterFromToken((byte)(registerToken & 0x7), X86RegisterSize.Dword);
            operand.OperandUsage = GetOperandType(size);
            operand.Value = register;

            // EBP register is replaced by a direct address.
            if (modifier == X86RegOrMemModifier.RegisterPointer && register == X86Register.Ebp)
            {
                operand.Value = _reader.ReadUInt32();
                return operand;
            }

            // ESP register are replaced by a scaled index operand.
            if (register == X86Register.Esp)
                MakeScaledIndexOperandFromToken(operand, _reader.ReadByte());

            // Read correction based on modifier.
            switch (modifier)
            {
                case X86RegOrMemModifier.RegisterDispShortPointer:
                    operand.Offset = _reader.ReadSByte();
                    operand.OffsetType = X86OffsetType.Short;
                    break;
                case X86RegOrMemModifier.RegisterDispLongPointer:
                    operand.Offset = _reader.ReadInt32();
                    operand.OffsetType = X86OffsetType.Long;
                    break;
            }

            return operand;
        }