Re: Byte-compiling the line specs

[Felix Lee <flee@teleport.com>]

I couldn't figure out what I did the first time, so I started over,
taking careful notes.

ignoring garbage collection, princ is faster up to about 5 arguments.
after that, (insert (format "")) is faster.  this is mostly because
princ requires a funcall.  if a bytecode for princ were added, princ
would probably always win.

on the other hand, princ doesn't generate garbage, so it's probably an
amortized win for up to I-don't-know-how-many arguments.

on the other other hand, realistic formats are somewhat complicated.
throw in something like "%5d", then the funcall costs increase.

(side note.  it looks like the insertN bytecode is only a marginal win
over N inserts)

here's my timings (emacs 19.29, i586-unknown-linux).  garbage
collection was effectively disabled for these runs.  the format is
	(code
	 iterations
	 (65536*sec sec msec))

;; null loop
((t)
 50000
 (0 0 212964))

;; (defun call-nil ())
(((call-nil))
 50000
 (0 0 819474))

;; (defun call-identity (x) x)
(((call-identity n))
 50000
 (0 1 19664))



;; basic insert
(((insert "99999"))
 50000
 (0 0 550920))

(((insert "a" "b"))
 50000
 (0 0 743891))

(((insert a b))
 50000
 (0 0 777184))

(((insert "a") (insert "b"))
 50000
 (0 0 766438))


;; insertN v. N inserts
(((insert "a" "b" "c" "d" "e" "f" "g" "h"))
 50000
 (0 1 882816))

(((insert "a") (insert "b") (insert "c") (insert "d")
  (insert "e") (insert "f") (insert "g") (insert "h"))
 50000
 (0 2 128370))


;; princ
(((princ 99999))
 50000
 (0 5 641750))

;; calling a function that calls princ.
(((call-princ 99999))
 50000
 (0 7 402069))

(((insert
   (number-to-string 99999)))
 50000
 (0 6 807297))


;; princ v. format comparisons.

(((princ 99999) (insert "a"))
 50000
 (0 6 484584))

(((format "%d%s" 99999 "a"))
 50000
 (0 7 557146))

(((insert (format "%d%s" 99999 "a")))
 50000
 (0 8 985531))


(((princ 99999) (insert "a") (princ 99999) (insert "b"))
 50000
 (0 12 156523))

(((format "%d%s%d%s" 99999 "a" 99999 "b"))
 50000
 (0 12 377714))

(((insert (format "%d%s%d%s" 99999 "a" 99999 "b")))
 50000
 (0 13 873505))


(((format "%d%s%d%s%d%s" 99999 "a" 99999 "b" 99999 "c"))
 5000
 (0 1 534841))

(((insert (format "%d%s%d%s%d%s" 99999 "a" 99999 "b" 99999 "c")))
 5000
 (0 1 669104))

(((princ 99999) (insert "a")
  (princ 99999) (insert "b")
  (princ 99999) (insert "c"))
 5000
 (0 1 792144))