- ;; CMU CL had a KILL slot here, documented as "set used by
- ;; constraint propagation", which was used in constraint propagation
- ;; as a list of LAMBDA-VARs killed, and in copy propagation as an
- ;; SSET, representing I dunno what. I (WHN) found this confusing,
- ;; and furthermore it caused type errors when I was trying to make
- ;; the compiler produce fully general LAMBDA functions directly
- ;; (instead of doing as CMU CL always did, producing extra little
- ;; functions which return the LAMDBA you need) and therefore taking
- ;; a new path through the compiler. So I split this into two:
- ;; KILL-LIST = list of LAMBDA-VARs killed, used in constraint propagation
- ;; KILL-SSET = an SSET value, used in copy propagation
- (kill-list nil :type list)
- (kill-sset nil :type (or sset null))
+ ;; in constraint propagation: list of LAMBDA-VARs killed in this block
+ ;; in copy propagation: list of killed TNs
+ (kill nil)