bsdperimeter/pfsense — comment on commit 1716682b1d1a6efa6e97bb0874e89e6132c55dfd
File:  line 0
By efonne:

It is stored for access to it from further calls to this function so that it is only done once during the filter reload. This revision also removes the irrelevant lines from the output during that one time instead of checking for it later so it has less work to do the next time it is called.

It is probably faster to do this than actually calling up an external command to check the routing table every time it has to check something (which could be many times in a large rule list). If there is (or will be) some way to easily work off only the config, I wouldn't be against changing it to do so, though.