First of all, stop and ask yourself why you want to make things so complicated. Are you trying to break some sort of speed record for port manipulation?
Still, look at this file: arduino\hardware\arduino\sam\variants\arduino_due_x\variant.cpp in that file is the definition of g_APinDescription. In there you can find the values... sort of. Even that file uses symbolic names. You really are better off just using the symbolic names. Going straight to the actual addresses doesn't really gain you anything other than making your code extremely hard to follow and/or understand.