code: final void _emitOpCode(int opCode) {
          // instruction prefix
          if ((opCode & 0xFF000000) != 0) {
              _emitByte((byte) ((opCode & 0xFF000000) >> 24));
          }
          // instruction opcodes
          if ((opCode & 0x00FF0000) != 0) {
              _emitByte((byte) ((opCode & 0x00FF0000) >> 16));
          }
          if ((opCode & 0x0000FF00) != 0) {
              _emitByte((byte) ((opCode & 0x0000FF00) >> 8));
          }
          // last opcode is always emitted (can be also 0x00)
          _emitByte((byte) (opCode & 0x000000FF));
      }
docs: ! @brief Emit single @a opCode without operands.