Move side-effect-free and pure declarations to function definitions

Some Lisp functions still had their `side-effect-free` and `pure`
properties declared in byte-opt.el; do it at their definition instead.
The lists in byte-opt.el now only contain functions implemented in C
and function aliases.

* lisp/emacs-lisp/byte-opt.el (side-effect-free-fns)
(side-effect-and-error-free-fns, pure-fns):
Remove functions whose properties are now declared elsewhere
and some obsolete entries.
* lisp/custom.el (custom-variable-p):
* lisp/emacs-lisp/lisp.el (buffer-end):
* lisp/emacs-lisp/regexp-opt.el (regexp-opt):
* lisp/env.el (getenv):
* lisp/simple.el (count-lines, mark, string-empty-p, lax-plist-get):
* lisp/subr.el (ignore, always, zerop, fixnump, bignump, lsh, last)
(eventp, mouse-movement-p, log10, memory-limit, string-greaterp)
(interactive-p):
* lisp/window.el (get-lru-window, get-largest-window, (window-edges)
(window-body-edges, window-pixel-edges, window-body-pixel-edges)
(window-absolute-pixel-edges, window-absolute-body-pixel-edges)
(one-window-p):
Declare functions `side-effect-free` and/or `pure` as appropriate.

1 files changed, 18 insertions, 6 deletions

diff --git a/lisp/subr.el b/lisp/subr.el
index a1397fa6781..819d2a51101 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -422,7 +422,9 @@ PREFIX is a string, and defaults to \"g\"."
   "Do nothing and return nil.
 This function accepts any number of ARGUMENTS, but ignores them.
 Also see `always'."
-  (declare (completion ignore))
+  ;; Not declared `side-effect-free' because we don't want calls to it
+  ;; elided; see `byte-compile-ignore'.
+  (declare (pure t) (completion ignore))
   (interactive)
   nil)
 
@@ -430,6 +432,7 @@ Also see `always'."
   "Do nothing and return t.
 This function accepts any number of ARGUMENTS, but ignores them.
 Also see `ignore'."
+  (declare (pure t) (side-effect-free error-free))
   t)
 
 ;; Signal a compile-error if the first arg is missing.
@@ -509,16 +512,19 @@ was called."
   "Return t if NUMBER is zero."
   ;; Used to be in C, but it's pointless since (= 0 n) is faster anyway because
   ;; = has a byte-code.
-  (declare (compiler-macro (lambda (_) `(= 0 ,number))))
+  (declare (pure t) (side-effect-free t)
+           (compiler-macro (lambda (_) `(= 0 ,number))))
   (= 0 number))
 
 (defun fixnump (object)
   "Return t if OBJECT is a fixnum."
+  (declare (side-effect-free error-free))
   (and (integerp object)
        (<= most-negative-fixnum object most-positive-fixnum)))
 
 (defun bignump (object)
   "Return t if OBJECT is a bignum."
+  (declare (side-effect-free error-free))
   (and (integerp object) (not (fixnump object))))
 
 (defun lsh (value count)
@@ -533,7 +539,8 @@ instead."
             (lambda (form)
               (macroexp-warn-and-return
                (format-message "avoid `lsh'; use `ash' instead")
-               form '(suspicious lsh) t form))))
+               form '(suspicious lsh) t form)))
+           (side-effect-free t))
   (when (and (< value 0) (< count 0))
     (when (< value most-negative-fixnum)
       (signal 'args-out-of-range (list value count)))
@@ -706,7 +713,7 @@ instead."
 If LIST is nil, return nil.
 If N is non-nil, return the Nth-to-last link of LIST.
 If N is bigger than the length of LIST, return LIST."
-  (declare (side-effect-free t))
+  (declare (pure t) (side-effect-free t))    ; pure up to mutation
   (if n
       (and (>= n 0)
            (let ((m (safe-length list)))
@@ -1525,6 +1532,7 @@ See also `current-global-map'.")
 
 (defun eventp (object)
   "Return non-nil if OBJECT is an input event or event object."
+  (declare (pure t) (side-effect-free error-free))
   (or (integerp object)
       (and (if (consp object)
                (setq object (car object))
@@ -1587,6 +1595,7 @@ in the current Emacs session, then this function may return nil."
 
 (defsubst mouse-movement-p (object)
   "Return non-nil if OBJECT is a mouse movement event."
+  (declare (side-effect-free error-free))
   (eq (car-safe object) 'mouse-movement))
 
 (defun mouse-event-p (object)
@@ -1859,7 +1868,7 @@ be a list of the form returned by `event-start' and `event-end'."
 
 (defun log10 (x)
   "Return (log X 10), the log base 10 of X."
-  (declare (obsolete log "24.4"))
+  (declare (side-effect-free t) (obsolete log "24.4"))
   (log x 10))
 
 (set-advertised-calling-convention
@@ -2983,6 +2992,7 @@ It can be retrieved with `(process-get PROCESS PROPNAME)'."
 
 (defun memory-limit ()
   "Return an estimate of Emacs virtual memory usage, divided by 1024."
+  (declare (side-effect-free error-free))
   (let ((default-directory temporary-file-directory))
     (or (cdr (assq 'vsize (process-attributes (emacs-pid)))) 0)))
 
@@ -5544,6 +5554,7 @@ consisting of STR followed by an invisible left-to-right mark
   "Return non-nil if STRING1 is greater than STRING2 in lexicographic order.
 Case is significant.
 Symbols are also allowed; their print names are used instead."
+  (declare (pure t) (side-effect-free t))
   (string-lessp string2 string1))
 
 
@@ -6187,7 +6198,8 @@ To test whether a function can be called interactively, use
 `commandp'."
   ;; Kept around for now.  See discussion at:
   ;; https://lists.gnu.org/r/emacs-devel/2020-08/msg00564.html
-  (declare (obsolete called-interactively-p "23.2"))
+  (declare (obsolete called-interactively-p "23.2")
+           (side-effect-free error-free))
   (called-interactively-p 'interactive))
 
 (defun internal-push-keymap (keymap symbol)