private static ulong ReadEncodedAddress()

in src/BinaryParsers/ElfBinary/Dwarf/DwarfCommonInformationEntry.cs [363:463]
82 lines of code
23 McCabe index (conditional complexity)

        private static ulong ReadEncodedAddress(DwarfMemoryReader data, DwarfExceptionHandlingEncoding encoding, DwarfExceptionHandlingFrameParsingInput input)
        {
            bool signExtendValue = false;
            ulong baseAddress = 0;

            switch (encoding & DwarfExceptionHandlingEncoding.Modifiers)
            {
                case DwarfExceptionHandlingEncoding.PcRelative:
                    signExtendValue = true;
                    baseAddress = (ulong)data.Position;
                    if (input.PcRelativeAddress != ulong.MaxValue)
                    {
                        baseAddress += input.PcRelativeAddress;
                    }
                    break;

                case DwarfExceptionHandlingEncoding.TextRelative:
                    signExtendValue = true;
                    if (input.TextAddress != ulong.MaxValue)
                    {
                        baseAddress = input.TextAddress;
                    }
                    break;

                case DwarfExceptionHandlingEncoding.DataRelative:
                    signExtendValue = true;
                    if (input.DataAddress != ulong.MaxValue)
                    {
                        baseAddress = input.DataAddress;
                    }
                    break;

                case DwarfExceptionHandlingEncoding.FunctionRelative:
                    signExtendValue = true;
                    break;

                case DwarfExceptionHandlingEncoding.Aligned:
                {
                    int alignment = data.Position % input.DefaultAddressSize;

                    if (alignment > 0)
                    {
                        data.Position += input.DefaultAddressSize - alignment;
                    }
                }
                break;
            }

            ulong address = 0;

            switch (encoding & DwarfExceptionHandlingEncoding.Mask)
            {
                case DwarfExceptionHandlingEncoding.Signed:
                case DwarfExceptionHandlingEncoding.AbsolutePointer:
                    address = data.ReadUlong(input.DefaultAddressSize);
                    break;

                case DwarfExceptionHandlingEncoding.UnsignedData2:
                    address = data.ReadUshort();
                    break;

                case DwarfExceptionHandlingEncoding.UnsignedData4:
                    address = data.ReadUint();
                    break;

                case DwarfExceptionHandlingEncoding.SignedData8:
                case DwarfExceptionHandlingEncoding.UnsignedData8:
                    address = data.ReadUlong();
                    break;

                case DwarfExceptionHandlingEncoding.Uleb128:
                    address = data.LEB128();
                    break;

                case DwarfExceptionHandlingEncoding.Sleb128:
                    address = data.SLEB128();
                    break;

                case DwarfExceptionHandlingEncoding.SignedData2:
                    address = (ulong)(long)(short)data.ReadUshort();
                    break;

                case DwarfExceptionHandlingEncoding.SignedData4:
                    address = (ulong)(long)(int)data.ReadUint();
                    break;
            }

            if (signExtendValue && input.DefaultAddressSize < System.Runtime.InteropServices.Marshal.SizeOf(address.GetType()))
            {
                ulong sign_bit = 1UL << ((input.DefaultAddressSize * 8) - 1);

                if ((sign_bit & address) != 0)
                {
                    ulong mask = ~sign_bit + 1;

                    address |= mask;
                }
            }

            return baseAddress + address;
        }