;;; Copyright (c) 1991, 1994 Free Software Foundation, Inc.
-;; Author: Jamie Zawinski <jwz@netscape.com>
+;; Author: Jamie Zawinski <jwz@jwz.org>
;; Hallvard Furuseth <hbf@ulrik.uio.no>
;; Keywords: internal
;; General Public License for more details.
;; You should have received a copy of the GNU General Public License
-;; along with XEmacs; see the file COPYING. If not, write to the
+;; along with XEmacs; see the file COPYING. If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.
;; You can, however, make a faster pig."
;;
;; Or, to put it another way, the emacs byte compiler is a VW Bug. This code
-;; makes it be a VW Bug with fuel injection and a turbocharger... You're
+;; makes it be a VW Bug with fuel injection and a turbocharger... You're
;; still not going to make it go faster than 70 mph, but it might be easier
;; to get it there.
;;
;; Simple defsubsts often produce forms like
;; (let ((v1 (f1)) (v2 (f2)) ...)
;; (FN v1 v2 ...))
-;; It would be nice if we could optimize this to
+;; It would be nice if we could optimize this to
;; (FN (f1) (f2) ...)
;; but we can't unless FN is dynamically-safe (it might be dynamically
;; referring to the bindings that the lambda arglist established.)
;; One of the uncountable lossages introduced by dynamic scope...
;;
-;; Maybe there should be a control-structure that says "turn on
+;; Maybe there should be a control-structure that says "turn on
;; fast-and-loose type-assumptive optimizations here." Then when
;; we see a form like (car foo) we can from then on assume that
;; the variable foo is of type cons, and optimize based on that.
-;; But, this won't win much because of (you guessed it) dynamic
+;; But, this won't win much because of (you guessed it) dynamic
;; scope. Anything down the stack could change the value.
;; (Another reason it doesn't work is that it is perfectly valid
;; to call car with a null argument.) A better approach might
;;
;; However, if there was even a single let-binding around the COND,
;; it could not be byte-compiled, because there would be an "unbind"
-;; byte-op between the final "call" and "return." Adding a
+;; byte-op between the final "call" and "return." Adding a
;; Bunbind_all byteop would fix this.
;;
;; (defun foo (x y z) ... (foo a b c))
;;
;; Wouldn't it be nice if Emacs Lisp had lexical scope.
;;
-;; Idea: the form (lexical-scope) in a file means that the file may be
-;; compiled lexically. This proclamation is file-local. Then, within
+;; Idea: the form (lexical-scope) in a file means that the file may be
+;; compiled lexically. This proclamation is file-local. Then, within
;; that file, "let" would establish lexical bindings, and "let-dynamic"
;; would do things the old way. (Or we could use CL "declare" forms.)
;; We'd have to notice defvars and defconsts, since those variables should
;; in the file being compiled (doing a boundp check isn't good enough.)
;; Fdefvar() would have to be modified to add something to the plist.
;;
-;; A major disadvantage of this scheme is that the interpreter and compiler
-;; would have different semantics for files compiled with (dynamic-scope).
+;; A major disadvantage of this scheme is that the interpreter and compiler
+;; would have different semantics for files compiled with (dynamic-scope).
;; Since this would be a file-local optimization, there would be no way to
-;; modify the interpreter to obey this (unless the loader was hacked
+;; modify the interpreter to obey this (unless the loader was hacked
;; in some grody way, but that's a really bad idea.)
;;
;; HA! RMS removed the following paragraph from his version of
;; byte-optimize.el.
;;
;; Really the Right Thing is to make lexical scope the default across
-;; the board, in the interpreter and compiler, and just FIX all of
+;; the board, in the interpreter and compiler, and just FIX all of
;; the code that relies on dynamic scope of non-defvarred variables.
;; Other things to consider:
;; error free also they may act as true-constants.
;;(disassemble #'(lambda (x) (and (point) (foo))))
-;; When
+;; When
;; - all but one arguments to a function are constant
;; - the non-constant argument is an if-expression (cond-expression?)
;; then the outer function can be distributed. If the guarding
(cons fn (cdr form)))))))
;;; ((lambda ...) ...)
-;;;
+;;;
(defun byte-compile-unfold-lambda (form &optional name)
(or name (setq name "anonymous lambda"))
(let ((lambda (car form))
(byte-compile-warn
"attempt to open-code %s with too many arguments" name))
form)
- (let ((newform
+ (let ((newform
(if bindings
(cons 'let (cons (nreverse bindings) body))
(cons 'progn body))))
(cons (byte-optimize-form (nth 1 form) t)
(cons (byte-optimize-form (nth 2 form) for-effect)
(byte-optimize-body (cdr (cdr (cdr form))) t)))))
-
+
((memq fn '(save-excursion save-restriction save-current-buffer))
;; those subrs which have an implicit progn; it's not quite good
;; enough to treat these like normal function calls.
;; This can turn (save-excursion ...) into (save-excursion) which
;; will be optimized away in the lap-optimize pass.
(cons fn (byte-optimize-body (cdr form) for-effect)))
-
+
((eq fn 'with-output-to-temp-buffer)
;; this is just like the above, except for the first argument.
(cons fn
(cons
(byte-optimize-form (nth 1 form) nil)
(byte-optimize-body (cdr (cdr form)) for-effect))))
-
+
((eq fn 'if)
(cons fn
(cons (byte-optimize-form (nth 1 form) nil)
(cons
(byte-optimize-form (nth 2 form) for-effect)
(byte-optimize-body (nthcdr 3 form) for-effect)))))
-
+
((memq fn '(and or)) ; remember, and/or are control structures.
;; take forms off the back until we can't any more.
;; In the future it could conceivably be a problem that the
(byte-compile-log
" all subforms of %s called for effect; deleted" form))
(and backwards
+ ;; Now optimize the rest of the forms. We need the return
+ ;; values. We already did the car.
+ (setcdr backwards
+ (mapcar 'byte-optimize-form (cdr backwards)))
(cons fn (nreverse backwards))))
(cons fn (mapcar 'byte-optimize-form (cdr form)))))
(byte-compile-warn "misplaced interactive spec: %s"
(prin1-to-string form))
nil)
-
+
((memq fn '(defun defmacro function
condition-case save-window-excursion))
;; These forms are compiled as constants or by breaking out
(cons fn
(cons (byte-optimize-form (nth 1 form) for-effect)
(cdr (cdr form)))))
-
+
((eq fn 'catch)
;; the body of a catch is compiled (and thus optimized) as a
;; top-level form, so don't do it here. The tag is never
(setq form (macroexpand form
byte-compile-macro-environment))))
(byte-optimize-form form for-effect))
-
+
((not (symbolp fn))
(or (eq 'mocklisp (car-safe fn)) ; ha!
(byte-compile-warn "%s is a malformed function"
;; appending a nil here might not be necessary, but it can't hurt.
(byte-optimize-form
(cons 'progn (append (cdr form) '(nil))) t))
-
+
(t
;; Otherwise, no args can be considered to be for-effect,
;; even if the called function is for-effect, because we
((keywordp ,form))))
;; If the function is being called with constant numeric args,
-;; evaluate as much as possible at compile-time. This optimizer
+;; evaluate as much as possible at compile-time. This optimizer
;; assumes that the function is associative, like + or *.
(defun byte-optimize-associative-math (form)
(let ((args nil)
(setq form (byte-optimize-delay-constants-math form 1 '+))
(if (memq 0 form) (setq form (delq 0 (copy-sequence form))))
;;(setq form (byte-optimize-associative-two-args-math form))
- (cond ((null (cdr form))
- (condition-case ()
- (eval form)
- (error form)))
-
- ;; `add1' and `sub1' are a marginally fewer instructions
- ;; than `plus' and `minus', so use them when possible.
- ((and (null (nthcdr 3 form))
- (eq (nth 2 form) 1))
- (list '1+ (nth 1 form))) ; (+ x 1) --> (1+ x)
- ((and (null (nthcdr 3 form))
- (eq (nth 1 form) 1))
- (list '1+ (nth 2 form))) ; (+ 1 x) --> (1+ x)
- ((and (null (nthcdr 3 form))
- (eq (nth 2 form) -1))
- (list '1- (nth 1 form))) ; (+ x -1) --> (1- x)
- ((and (null (nthcdr 3 form))
- (eq (nth 1 form) -1))
- (list '1- (nth 2 form))) ; (+ -1 x) --> (1- x)
-;;; It is not safe to delete the function entirely
-;;; (actually, it would be safe if we know the sole arg
-;;; is not a marker).
-;; ((null (cdr (cdr form))) (nth 1 form))
- (t form)))
+ (case (length (cdr form))
+ ((0) ; (+)
+ (condition-case ()
+ (eval form)
+ (error form)))
+
+ ;; It is not safe to delete the function entirely
+ ;; (actually, it would be safe if we knew the sole arg
+ ;; is not a marker).
+ ;; ((1)
+ ;; (nth 1 form))
+
+ ((2) ; (+ x y)
+ (byte-optimize-predicate
+ (cond
+ ;; `add1' and `sub1' are a marginally fewer instructions
+ ;; than `plus' and `minus', so use them when possible.
+ ((eq (nth 1 form) 1) `(1+ ,(nth 2 form))) ; (+ 1 x) --> (1+ x)
+ ((eq (nth 2 form) 1) `(1+ ,(nth 1 form))) ; (+ x 1) --> (1+ x)
+ ((eq (nth 1 form) -1) `(1- ,(nth 2 form))) ; (+ -1 x) --> (1- x)
+ ((eq (nth 2 form) -1) `(1- ,(nth 1 form))) ; (+ x -1) --> (1- x)
+ (t form))))
+
+ (t (byte-optimize-predicate form))))
(defun byte-optimize-minus (form)
;; Put constants at the end, except the last constant.
(setq form (byte-optimize-delay-constants-math form 2 '+))
- ;; Now only first and last element can be a number.
- (let ((last (car (reverse (nthcdr 3 form)))))
+ ;; Now only first and last element can be an integer.
+ (let ((last (last (nthcdr 3 form))))
(cond ((eq 0 last)
;; (- x y ... 0) --> (- x y ...)
(setq form (copy-sequence form))
(numberp last))
(setq form (nconc (list '- (- (nth 1 form) last) (nth 2 form))
(delq last (copy-sequence (nthcdr 3 form))))))))
- (setq form
-;;; It is not safe to delete the function entirely
-;;; (actually, it would be safe if we know the sole arg
-;;; is not a marker).
-;;; (if (eq (nth 2 form) 0)
-;;; (nth 1 form) ; (- x 0) --> x
- (byte-optimize-predicate
- (if (and (null (cdr (cdr (cdr form))))
- (eq (nth 1 form) 0)) ; (- 0 x) --> (- x)
- (cons (car form) (cdr (cdr form)))
- form))
-;;; )
- )
-
- ;; `add1' and `sub1' are a marginally fewer instructions than `plus'
- ;; and `minus', so use them when possible.
- (cond ((and (null (nthcdr 3 form))
- (eq (nth 2 form) 1))
- (list '1- (nth 1 form))) ; (- x 1) --> (1- x)
- ((and (null (nthcdr 3 form))
- (eq (nth 2 form) -1))
- (list '1+ (nth 1 form))) ; (- x -1) --> (1+ x)
- (t
- form))
- )
+
+ (case (length (cdr form))
+ ((0) ; (-)
+ (condition-case ()
+ (eval form)
+ (error form)))
+
+ ;; It is not safe to delete the function entirely
+ ;; (actually, it would be safe if we knew the sole arg
+ ;; is not a marker).
+ ;; ((1)
+ ;; (nth 1 form)
+
+ ((2) ; (+ x y)
+ (byte-optimize-predicate
+ (cond
+ ;; `add1' and `sub1' are a marginally fewer instructions than `plus'
+ ;; and `minus', so use them when possible.
+ ((eq (nth 2 form) 1) `(1- ,(nth 1 form))) ; (- x 1) --> (1- x)
+ ((eq (nth 2 form) -1) `(1+ ,(nth 1 form))) ; (- x -1) --> (1+ x)
+ ((eq (nth 1 form) 0) `(- ,(nth 2 form))) ; (- 0 x) --> (- x)
+ (t form))))
+
+ (t (byte-optimize-predicate form))))
(defun byte-optimize-multiply (form)
(setq form (byte-optimize-delay-constants-math form 1 '*))
- ;; If there is a constant in FORM, it is now the last element.
+ ;; If there is a constant integer in FORM, it is now the last element.
(cond ((null (cdr form)) 1)
;;; It is not safe to delete the function entirely
;;; (actually, it would be safe if we know the sole arg
;;; is not a marker or if it appears in other arithmetic).
;;; ((null (cdr (cdr form))) (nth 1 form))
- ((let ((last (car (reverse form))))
- (cond ((eq 0 last) (cons 'progn (cdr form)))
- ((eq 1 last) (delq 1 (copy-sequence form)))
- ((eq -1 last) (list '- (delq -1 (copy-sequence form))))
- ((and (eq 2 last)
- (memq t (mapcar 'symbolp (cdr form))))
- (prog1 (setq form (delq 2 (copy-sequence form)))
- (while (not (symbolp (car (setq form (cdr form))))))
- (setcar form (list '+ (car form) (car form)))))
- (form))))))
-
-(defsubst byte-compile-butlast (form)
- (nreverse (cdr (reverse form))))
+ ((let ((last (last form)))
+ (byte-optimize-predicate
+ (cond ((eq 0 last) (cons 'progn (cdr form)))
+ ((eq 1 last) (delq 1 (copy-sequence form)))
+ ((eq -1 last) (list '- (delq -1 (copy-sequence form))))
+ ((and (eq 2 last)
+ (memq t (mapcar 'symbolp (cdr form))))
+ (prog1 (setq form (delq 2 (copy-sequence form)))
+ (while (not (symbolp (car (setq form (cdr form))))))
+ (setcar form (list '+ (car form) (car form)))))
+ (form)))))))
(defun byte-optimize-divide (form)
(setq form (byte-optimize-delay-constants-math form 2 '*))
- (let ((last (car (reverse (cdr (cdr form))))))
+ ;; If there is a constant integer in FORM, it is now the last element.
+ (let ((last (last (cdr (cdr form)))))
(if (numberp last)
(cond ((= (length form) 3)
(if (and (numberp (nth 1 form))
(error nil)))
(setq form (list 'progn (/ (nth 1 form) last)))))
((= last 1)
- (setq form (byte-compile-butlast form)))
+ (setq form (butlast form)))
((numberp (nth 1 form))
(setq form (cons (car form)
(cons (/ (nth 1 form) last)
- (byte-compile-butlast (cdr (cdr form)))))
+ (butlast (cdr (cdr form)))))
last nil))))
- (cond
+ (cond
;;; ((null (cdr (cdr form)))
;;; (nth 1 form))
- ((eq (nth 1 form) 0)
- (append '(progn) (cdr (cdr form)) '(0)))
- ((eq last -1)
- (list '- (if (nthcdr 3 form)
- (byte-compile-butlast form)
- (nth 1 form))))
- (form))))
+ ((eq (nth 1 form) 0)
+ (append '(progn) (cdr (cdr form)) '(0)))
+ ((eq last -1)
+ (list '- (if (nthcdr 3 form)
+ (butlast form)
+ (nth 1 form))))
+ (form))))
(defun byte-optimize-logmumble (form)
(setq form (byte-optimize-delay-constants-math form 1 (car form)))
(put 'stringp 'byte-optimizer 'byte-optimize-predicate)
(put 'string< 'byte-optimizer 'byte-optimize-predicate)
(put 'string-lessp 'byte-optimizer 'byte-optimize-predicate)
+(put 'length 'byte-optimizer 'byte-optimize-predicate)
(put 'logand 'byte-optimizer 'byte-optimize-logmumble)
(put 'logior 'byte-optimizer 'byte-optimize-logmumble)
(put 'cdr-safe 'byte-optimizer 'byte-optimize-predicate)
-;; I'm not convinced that this is necessary. Doesn't the optimizer loop
+;; I'm not convinced that this is necessary. Doesn't the optimizer loop
;; take care of this? - Jamie
;; I think this may some times be necessary to reduce eg. (quote 5) to 5,
;; so arithmetic optimizers recognize the numeric constant. - Hallvard
(put 'if 'byte-optimizer 'byte-optimize-if)
(put 'while 'byte-optimizer 'byte-optimize-while)
+;; Remove any reason for avoiding `char-before'.
+(defun byte-optimize-char-before (form)
+ `(char-after (1- ,(or (nth 1 form) '(point))) ,@(cdr (cdr form))))
+
+(put 'char-before 'byte-optimizer 'byte-optimize-char-before)
+
;; byte-compile-negation-optimizer lives in bytecomp.el
;(put '/= 'byte-optimizer 'byte-compile-negation-optimizer)
(put 'atom 'byte-optimizer 'byte-compile-negation-optimizer)
(setq form (list 'cdr form)))
form)))
\f
-;;; enumerating those functions which need not be called if the returned
+;;; enumerating those functions which need not be called if the returned
;;; value is not used. That is, something like
;;; (progn (list (something-with-side-effects) (yow))
;;; (foo))
length log log10 logand logb logior lognot logxor lsh
marker-buffer max member memq min mod
next-window nth nthcdr number-to-string
- parse-colon-path previous-window
+ parse-colon-path plist-get previous-window
radians-to-degrees rassq regexp-quote reverse round
sin sqrt string< string= string-equal string-lessp string-to-char
string-to-int string-to-number substring symbol-plist
abs expt signum last butlast ldiff
pairlis gcd lcm
isqrt floor* ceiling* truncate* round* mod* rem* subseq
- list-length get* getf
+ list-length getf
))
(side-effect-and-error-free-fns
'(arrayp atom
byte-current-buffer byte-interactive-p))
(defconst byte-compile-side-effect-free-ops
- (nconc
+ (nconc
'(byte-varref byte-nth byte-memq byte-car byte-cdr byte-length byte-aref
byte-symbol-value byte-get byte-concat2 byte-concat3 byte-sub1 byte-add1
byte-eqlsign byte-gtr byte-lss byte-leq byte-geq byte-diff byte-negate
;;; varbind pop-up-windows
;;; not
;;;
-;;; we break the program, because it will appear that pop-up-windows and
+;;; we break the program, because it will appear that pop-up-windows and
;;; old-pop-ups are not EQ when really they are. So we have to know what
;;; the BOOL variables are, and not perform this optimization on them.
;;;
;; goto-X-if-non-nil goto-Y X: --> goto-Y-if-nil X:
;;
;; it is wrong to do the same thing for the -else-pop variants.
- ;;
+ ;;
((and (or (eq 'byte-goto-if-nil (car lap0))
(eq 'byte-goto-if-not-nil (car lap0))) ; gotoX
(eq 'byte-goto (car lap1)) ; gotoY
str (concat str " %s")
i (1+ i))))
(if opt-p
- (let ((tagstr
+ (let ((tagstr
(if (eq 'TAG (car (car tmp)))
(format "%d:" (car (cdr (car tmp))))
(or (car tmp) ""))))
(byte-goto-if-not-nil-else-pop .
byte-goto-if-nil-else-pop))))
newtag)
-
+
(nth 1 newtag)
)
(setcdr tmp (cons (setcdr lap0 newtag) (cdr tmp)))
projects / chise / xemacs-chise.git.1 / blobdiff