Unrolling lists
Zhong Shao, John H. Reppy, Andrew W. Appel · 1994
Lists are ubiquitous in functional programs, thus supporting lists efficiently is a major concern to compiler writers for functional languages. Lists are normally represented as linked cons cells, with each cons cell containing a car (the data) and a cdr (the link); this is inefficient in the use of space, because 50% of the storage is used for links. Loops and recursions on lists are slow on modern machines because of the long chains of control dependencies (in checking for nil) and data dependencies (in fetching cdr fields).