func: function enter(bytes32 _passphrase)
      public
    {
      
      
      
      
      
      
      
      
      uint256 stipend;
      uint256 offset;
  
      uint256 key;
      uint256 upper;
      uint256 lower;
  
      stipend = 500000;
      stipend -= stipend % 8191;
  
      offset = 0x1e7b;
      stipend -= offset;
  
      upper = uint256(bytes4("fnoo")) << 32;
      lower = uint256(uint16(msg.sender));
  
      key = upper | lower;
  
      assert(uint32(key) == uint16(key));
      assert(uint32(key) != uint64(key));
      assert(uint32(key) == uint16(tx.origin));
  
      gatekeeper.enter.gas(stipend)(_passphrase, bytes8(key));
    }