There is unreachable code in A64DOpcodeBitfield::format: const char* A64DOpcodeBitfield::format() { ... if (opc() == 0x2 && immediateS() == (immediateR() + 1)) { // lsl ... return m_formatBuffer; } else if (!(opc() & 0x1) && ((immediateS() & 0x1f) == 0x1f) && (is64Bit() == (immediateS() >> 5))) { // asr/lsr ... return m_formatBuffer; } else if (immediateS() < immediateR()) { // bit field insert ... return m_formatBuffer; } else { // bit field extract ... return m_formatBuffer; } appendInstructionName(opName()); appendRegisterName(rd(), is64Bit()); appendSeparator(); appendRegisterName(rn(), is64Bit()); appendSeparator(); appendUnsignedImmediate(immediateR()); appendSeparator(); appendUnsignedImmediate(immediateS()); return m_formatBuffer; } Should this code be reachable somehow, or can it just be removed.