; Finale (with Hal)

; Last time: Interpretation (raising the machine to the level of Lisp)
; Today: Compilation (lowering Lisp to the machine language)
;    Simulation vs. Translation

; Hal describes a way to call compiled objects from the interpreter
; by using the same conventions in the compiler as in the interpreter.

; Remove unnecessary operations required for simulation:
; 10A:(12m38s) => 10A:(15m44s)

; 10A:(17m26s) More compiler-optimizations.
; 10A:(18m39s) Elimination of Redundancies: 3 operations remain.

; QUESTIONS 10A:(25m32s) BREAK

; (OP A1 A2)
;    -> compiler tasks:
; {compile OP ; result in FUN} -> MUST PRESERVE ENV
;
; {compile A1 ; result in VAL} -> MUST PRESERVE ENV
; (assign argl (cons (fetch val) '()))
;
; {compile A2 ; result in VAL} -> MUST PRESERVE ARGL
; (assign argl (cons (fetch val) (fetch argl)))
; ......

; 10A:(32m44s) The task of a compiler is to append code-sequences,
;           preserving register-values by observing the requirements of
;           its input-procedures and saving the needed ones (for later)
;           that would be modified by other procedures.
; 10A:(37m27s) Hal summarizes the requirements to make this possible.
; (END)