Fix a cacheing bug, which led to inordinately slow c-beginning-of-defun.

* lisp/progmodes/cc-defs.el (c-self-bind-state-cache): New macro.

* lisp/progmodes/cc-engine.el (c-ssb-lit-begin): Always call c-parse-state
rather than just using the cache variable c-state-cache.
(c-syntactic-skip-backward): Invoke c-self-bind-state-cache to isolate calls
to c-parse-state from other uses of the parse state cache.

* lisp/progmodes/cc-cmds.el (c-beginning-of-defun, c-end-of-defun): Invoke
c-self-bind-state-cache around the processing, replacing flawed bindings of
c-state-cache.

1 files changed, 124 insertions, 121 deletions

diff --git a/lisp/progmodes/cc-cmds.el b/lisp/progmodes/cc-cmds.el
index 6761de11700..764f44a8dd8 100644
--- a/lisp/progmodes/cc-cmds.el
+++ b/lisp/progmodes/cc-cmds.el
@@ -1594,69 +1594,70 @@ defun."
       (c-region-is-active-p)
       (push-mark))
 
-  (c-save-buffer-state
-      (beginning-of-defun-function end-of-defun-function
-       (start (point))
-       (paren-state (copy-tree (c-parse-state))) ; This must not share list
-					; structure with other users of c-state-cache.
-       (orig-point-min (point-min)) (orig-point-max (point-max))
-       lim			    ; Position of { which has been widened to.
-       where pos case-fold-search)
-
-    (save-restriction
-      (if (eq c-defun-tactic 'go-outward)
-	  (setq lim (c-widen-to-enclosing-decl-scope ; e.g. class, namespace.
-		     paren-state orig-point-min orig-point-max)))
-
-      ;; Move back out of any macro/comment/string we happen to be in.
-      (c-beginning-of-macro)
-      (setq pos (c-literal-limits))
-      (if pos (goto-char (car pos)))
-
-      (setq where (c-where-wrt-brace-construct))
-
-      (if (< arg 0)
-	  ;; Move forward to the closing brace of a function.
-	  (progn
-	    (if (memq where '(at-function-end outwith-function))
-		(setq arg (1+ arg)))
-	    (if (< arg 0)
-		(c-while-widening-to-decl-block
-		 (< (setq arg (- (c-forward-to-nth-EOF-} (- arg) where))) 0)))
-	    ;; Move forward to the next opening brace....
-	    (when (and (= arg 0)
-		       (progn
-			 (c-while-widening-to-decl-block
-			  (not (c-syntactic-re-search-forward "{" nil 'eob)))
-			 (eq (char-before) ?{)))
-	      (backward-char)
-	      ;; ... and backward to the function header.
-	      (c-beginning-of-decl-1)
-	      t))
-
-	;; Move backward to the opening brace of a function, making successively
-	;; larger portions of the buffer visible as necessary.
-	(when (> arg 0)
-	  (c-while-widening-to-decl-block
-	   (> (setq arg (c-backward-to-nth-BOF-{ arg where)) 0)))
-
-	(when (eq arg 0)
-	  ;; Go backward to this function's header.
-	  (c-beginning-of-decl-1)
-
-	  (setq pos (point))
-	  ;; We're now there, modulo comments and whitespace.
-	  ;; Try to be line oriented; position point at the closest
-	  ;; preceding boi that isn't inside a comment, but if we hit
-	  ;; the previous declaration then we use the current point
-	  ;; instead.
-	  (while (and (/= (point) (c-point 'boi))
-		      (c-backward-single-comment)))
-	  (if (/= (point) (c-point 'boi))
-	      (goto-char pos)))
-
-	(c-keep-region-active)
-	(= arg 0)))))
+  (c-self-bind-state-cache ; We must not share with other users of c-state-cache.
+   (c-save-buffer-state
+       (beginning-of-defun-function
+	end-of-defun-function
+	(start (point))
+	(paren-state (c-parse-state))
+	(orig-point-min (point-min)) (orig-point-max (point-max))
+	lim		    ; Position of { which has been widened to.
+	where pos case-fold-search)
+
+     (save-restriction
+       (if (eq c-defun-tactic 'go-outward)
+	   (setq lim (c-widen-to-enclosing-decl-scope ; e.g. class, namespace.
+		      paren-state orig-point-min orig-point-max)))
+
+       ;; Move back out of any macro/comment/string we happen to be in.
+       (c-beginning-of-macro)
+       (setq pos (c-literal-limits))
+       (if pos (goto-char (car pos)))
+
+       (setq where (c-where-wrt-brace-construct))
+
+       (if (< arg 0)
+	   ;; Move forward to the closing brace of a function.
+	   (progn
+	     (if (memq where '(at-function-end outwith-function))
+		 (setq arg (1+ arg)))
+	     (if (< arg 0)
+		 (c-while-widening-to-decl-block
+		  (< (setq arg (- (c-forward-to-nth-EOF-} (- arg) where))) 0)))
+	     ;; Move forward to the next opening brace....
+	     (when (and (= arg 0)
+			(progn
+			  (c-while-widening-to-decl-block
+			   (not (c-syntactic-re-search-forward "{" nil 'eob)))
+			  (eq (char-before) ?{)))
+	       (backward-char)
+	       ;; ... and backward to the function header.
+	       (c-beginning-of-decl-1)
+	       t))
+
+	 ;; Move backward to the opening brace of a function, making successively
+	 ;; larger portions of the buffer visible as necessary.
+	 (when (> arg 0)
+	   (c-while-widening-to-decl-block
+	    (> (setq arg (c-backward-to-nth-BOF-{ arg where)) 0)))
+
+	 (when (eq arg 0)
+	   ;; Go backward to this function's header.
+	   (c-beginning-of-decl-1)
+
+	   (setq pos (point))
+	   ;; We're now there, modulo comments and whitespace.
+	   ;; Try to be line oriented; position point at the closest
+	   ;; preceding boi that isn't inside a comment, but if we hit
+	   ;; the previous declaration then we use the current point
+	   ;; instead.
+	   (while (and (/= (point) (c-point 'boi))
+		       (c-backward-single-comment)))
+	   (if (/= (point) (c-point 'boi))
+	       (goto-char pos)))
+
+	 (c-keep-region-active)
+	 (= arg 0))))))
 
 (defun c-forward-to-nth-EOF-} (n where)
   ;; Skip to the closing brace of the Nth function after point.  If
@@ -1718,66 +1719,68 @@ the open-parenthesis that starts a defun; see `beginning-of-defun'."
       (c-region-is-active-p)
       (push-mark))
 
-  (c-save-buffer-state
-      (beginning-of-defun-function end-of-defun-function
-       (start (point))
-       (paren-state (copy-tree (c-parse-state))) ; This must not share list
-				  ; structure with other users of c-state-cache.
-       (orig-point-min (point-min)) (orig-point-max (point-max))
-       lim
-       where pos case-fold-search)
-
-    (save-restriction
-      (if (eq c-defun-tactic 'go-outward)
-	  (setq lim (c-widen-to-enclosing-decl-scope ; e.g. class, namespace
-		     paren-state orig-point-min orig-point-max)))
-
-      ;; Move back out of any macro/comment/string we happen to be in.
-      (c-beginning-of-macro)
-      (setq pos (c-literal-limits))
-      (if pos (goto-char (car pos)))
-
-      (setq where (c-where-wrt-brace-construct))
+  (c-self-bind-state-cache ; c-state-cache's list structure must not be shared
+			   ; with other users.
+   (c-save-buffer-state
+       (beginning-of-defun-function
+	end-of-defun-function
+	(start (point))
+	(paren-state (c-parse-state))
+	(orig-point-min (point-min)) (orig-point-max (point-max))
+	lim
+	where pos case-fold-search)
+
+     (save-restriction
+       (if (eq c-defun-tactic 'go-outward)
+	   (setq lim (c-widen-to-enclosing-decl-scope ; e.g. class, namespace
+		      paren-state orig-point-min orig-point-max)))
+
+       ;; Move back out of any macro/comment/string we happen to be in.
+       (c-beginning-of-macro)
+       (setq pos (c-literal-limits))
+       (if pos (goto-char (car pos)))
+
+       (setq where (c-where-wrt-brace-construct))
+
+       (if (< arg 0)
+	   ;; Move backwards to the } of a function
+	   (progn
+	     (if (memq where '(at-header outwith-function))
+		 (setq arg (1+ arg)))
+	     (if (< arg 0)
+		 (c-while-widening-to-decl-block
+		  (< (setq arg (- (c-backward-to-nth-BOF-{ (- arg) where))) 0)))
+	     (if (= arg 0)
+		 (c-while-widening-to-decl-block
+		  (progn (c-syntactic-skip-backward "^}")
+			 (not (eq (char-before) ?}))))))
+
+	 ;; Move forward to the } of a function
+	 (if (> arg 0)
+	     (c-while-widening-to-decl-block
+	      (> (setq arg (c-forward-to-nth-EOF-} arg where)) 0))))
+
+       ;; Do we need to move forward from the brace to the semicolon?
+       (when (eq arg 0)
+	 (if (c-in-function-trailer-p)	; after "}" of struct/enum, etc.
+	     (c-syntactic-re-search-forward ";"))
 
-      (if (< arg 0)
-	  ;; Move backwards to the } of a function
-	  (progn
-	    (if (memq where '(at-header outwith-function))
-		(setq arg (1+ arg)))
-	    (if (< arg 0)
-		(c-while-widening-to-decl-block
-		 (< (setq arg (- (c-backward-to-nth-BOF-{ (- arg) where))) 0)))
-	    (if (= arg 0)
-		(c-while-widening-to-decl-block
-		 (progn (c-syntactic-skip-backward "^}")
-			(not (eq (char-before) ?}))))))
-
-	;; Move forward to the } of a function
-	(if (> arg 0)
-	    (c-while-widening-to-decl-block
-	     (> (setq arg (c-forward-to-nth-EOF-} arg where)) 0))))
-
-      ;; Do we need to move forward from the brace to the semicolon?
-      (when (eq arg 0)
-	(if (c-in-function-trailer-p) ; after "}" of struct/enum, etc.
-	    (c-syntactic-re-search-forward ";"))
+	 (setq pos (point))
+	 ;; We're there now, modulo comments and whitespace.
+	 ;; Try to be line oriented; position point after the next
+	 ;; newline that isn't inside a comment, but if we hit the
+	 ;; next declaration then we use the current point instead.
+	 (while (and (not (bolp))
+		     (not (looking-at "\\s *$"))
+		     (c-forward-single-comment)))
+	 (cond ((bolp))
+	       ((looking-at "\\s *$")
+		(forward-line 1))
+	       (t
+		(goto-char pos))))
 
-	(setq pos (point))
-	;; We're there now, modulo comments and whitespace.
-	;; Try to be line oriented; position point after the next
-	;; newline that isn't inside a comment, but if we hit the
-	;; next declaration then we use the current point instead.
-	(while (and (not (bolp))
-		    (not (looking-at "\\s *$"))
-		    (c-forward-single-comment)))
-	(cond ((bolp))
-	      ((looking-at "\\s *$")
-	       (forward-line 1))
-	      (t
-	       (goto-char pos))))
-
-      (c-keep-region-active)
-      (= arg 0))))
+       (c-keep-region-active)
+       (= arg 0)))))
 
 (defun c-defun-name ()
   "Return the name of the current defun, or NIL if there isn't one.