Regarding the Fairchild Symbol IIr computer, and other obsolete architectures, I suggest reading the old book (out of print) by: Dan Siewiorek, G. Bell, A. Newell, "Computer Structures: Principles and Examples", printed in 1982 by McGraw Hill.
I've written a couple of notes, in the past about the Symbol
memory management that implemented variable length strings
in hardware, with primitive memory operations:
Assign Group, Store and Assign, Fetch and Follow.