Turn entry points into mere trampolines to the real code.
Forgive me for being thick, but hasn't that been "a thing" for decades? Even the BBC Micro did this (established "indirection" locations which could point to a routine anywhere in local, or even remote - e.g. second processor - memory), and I got the impression it was established practice back then.
Yes, yes, I know it's a distant, distant relative of the randomisation being talked about here, just brought back memories :-)