[Emacs-diffs] master 6b53887: Depessimize bits of CC Mode for long C macros.

[Alan Mackenzie]

branch: master
commit 6b5388794b4d1118cb4443cfccc1bdebb4fb1af4
Author: Alan Mackenzie <address@hidden>
Commit: Alan Mackenzie <address@hidden>

    Depessimize bits of CC Mode for long C macros.
    
    * lisp/progmodes/cc-engine.el (c-end-of-macro): Check for being in a
    degenerate zero length "macro", when setting the macro cache.
    (c-determine-+ve-limit): Add in a missing goto-char form for when start-pos 
is
    non-nil.
    (c-back-over-member-initializers): Add a search limit parameter.
    
    * lisp/progmodes/cc-fonts.el (c-get-fontification-context): Add a search 
limit
    to c-go-up-list-backward.
    (c-font-lock-cut-off-declarators): Add a search limit to
    c-back-over-member-initializers.
    
    * lisp/progmodes/cc-mode.el (c-before-change-check-unbalanced-strings): 
Don't
    set c-new-END to the end of logical line (which might be a long macro).
    (c-after-change-mark-abnormal-strings): Calculate end-hwm in place of the
    setting of c-new-END (above).  Use this as a search limit rather than
    c-new-END.
---
 lisp/progmodes/cc-engine.el | 76 ++++++++++++++++++++++++---------------------
 lisp/progmodes/cc-fonts.el  |  4 +--
 lisp/progmodes/cc-mode.el   | 17 +++++++---
 3 files changed, 56 insertions(+), 41 deletions(-)

diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el
index b121529..eeb7100 100644
--- a/lisp/progmodes/cc-engine.el
+++ b/lisp/progmodes/cc-engine.el
@@ -380,6 +380,8 @@ comment at the start of cc-engine.el for more info."
              nil)))
 
       (when (and (car c-macro-cache)
+                (> (point) (car c-macro-cache)) ; in case we have a
+                                                ; zero-sized region.
                 (bolp)
                 (not (eq (char-before (1- (point))) ?\\)))
        (setcdr c-macro-cache (point))
@@ -5646,6 +5648,7 @@ comment at the start of cc-engine.el for more info."
     (let ((pos (or start-pos (point)))
          (count how-far)
          (s (parse-partial-sexp (point) (point)))) ; null state
+      (goto-char pos)
       (while (and (not (eobp))
                  (> count 0))
        ;; Scan over counted characters.
@@ -8609,53 +8612,56 @@ comment at the start of cc-engine.el for more info."
        (throw 'level nil))
      (c-backward-syntactic-ws)))
 
-(defun c-back-over-member-initializers ()
+(defun c-back-over-member-initializers (&optional limit)
   ;; Test whether we are in a C++ member initializer list, and if so, go back
   ;; to the introducing ":", returning the position of the opening paren of
   ;; the function's arglist.  Otherwise return nil, leaving point unchanged.
-  (let ((here (point))
-       (paren-state (c-parse-state))
-       pos level-plausible at-top-level res)
-    ;; Assume tentatively that we're at the top level.  Try to go back to the
-    ;; colon we seek.
-    (setq res
-         (catch 'done
-           (setq level-plausible
-                 (catch 'level
-                   (c-backward-syntactic-ws)
-                   (when (memq (char-before) '(?\) ?}))
-                     (when (not (c-go-list-backward))
-                       (throw 'done nil))
-                     (c-backward-syntactic-ws))
-                   (when (c-back-over-compound-identifier)
-                     (c-backward-syntactic-ws))
-                   (c-back-over-list-of-member-inits)
-                   (and (eq (char-before) ?:)
-                        (save-excursion
-                          (c-backward-token-2)
-                          (not (looking-at c-:$-multichar-token-regexp)))
-                        (c-just-after-func-arglist-p))))
-
-           (while (and (not (and level-plausible
-                                 (setq at-top-level (c-at-toplevel-p))))
-                       (setq pos (c-pull-open-brace paren-state))) ; might be 
a paren.
+  ;; LIMIT, if non-nil, is a limit for the backward search.
+  (save-restriction
+    (if limit (narrow-to-region limit (point)))
+    (let ((here (point))
+         (paren-state (c-parse-state))
+         pos level-plausible at-top-level res)
+      ;; Assume tentatively that we're at the top level.  Try to go back to the
+      ;; colon we seek.
+      (setq res
+           (catch 'done
              (setq level-plausible
                    (catch 'level
-                     (goto-char pos)
-                     (c-backward-syntactic-ws)
-                     (when (not (c-back-over-compound-identifier))
-                       (throw 'level nil))
                      (c-backward-syntactic-ws)
+                     (when (memq (char-before) '(?\) ?}))
+                       (when (not (c-go-list-backward))
+                         (throw 'done nil))
+                       (c-backward-syntactic-ws))
+                     (when (c-back-over-compound-identifier)
+                       (c-backward-syntactic-ws))
                      (c-back-over-list-of-member-inits)
                      (and (eq (char-before) ?:)
                           (save-excursion
                             (c-backward-token-2)
                             (not (looking-at c-:$-multichar-token-regexp)))
-                          (c-just-after-func-arglist-p)))))
+                          (c-just-after-func-arglist-p))))
+
+             (while (and (not (and level-plausible
+                                   (setq at-top-level (c-at-toplevel-p))))
+                         (setq pos (c-pull-open-brace paren-state))) ; might 
be a paren.
+               (setq level-plausible
+                     (catch 'level
+                       (goto-char pos)
+                       (c-backward-syntactic-ws)
+                       (when (not (c-back-over-compound-identifier))
+                         (throw 'level nil))
+                       (c-backward-syntactic-ws)
+                       (c-back-over-list-of-member-inits)
+                       (and (eq (char-before) ?:)
+                            (save-excursion
+                              (c-backward-token-2)
+                              (not (looking-at c-:$-multichar-token-regexp)))
+                            (c-just-after-func-arglist-p)))))
 
-           (and at-top-level level-plausible)))
-    (or res (goto-char here))
-    res))
+             (and at-top-level level-plausible)))
+      (or res (goto-char here))
+      res)))
 
 (defun c-forward-class-decl ()
   "From the beginning of a struct/union, etc. move forward to
diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el
index c3dd8f8..cef2015 100644
--- a/lisp/progmodes/cc-fonts.el
+++ b/lisp/progmodes/cc-fonts.el
@@ -1204,7 +1204,7 @@ casts and declarations are fontified.  Used on level 2 
and higher."
          ((save-excursion
             (goto-char match-pos)
             (and (memq (char-before match-pos) '(?\( ?\,))
-                 (c-go-up-list-backward match-pos)
+                 (c-go-up-list-backward match-pos (c-determine-limit 500))
                  (eq (char-after) ?\()
                  (let ((type (c-get-char-property (point) 'c-type)))
                    (or (memq type '(c-decl-arg-start c-decl-type-start))
@@ -1605,7 +1605,7 @@ casts and declarations are fontified.  Used on level 2 
and higher."
          c-recognize-knr-p)            ; Strictly speaking, bogus, but it
                                        ; speeds up lisp.h tremendously.
       (save-excursion
-       (when (not (c-back-over-member-initializers))
+       (when (not (c-back-over-member-initializers (c-determine-limit 2000)))
          (unless (or (eobp)
                      (looking-at "\\s(\\|\\s)"))
            (forward-char))
diff --git a/lisp/progmodes/cc-mode.el b/lisp/progmodes/cc-mode.el
index 83c0e36..830dfca 100644
--- a/lisp/progmodes/cc-mode.el
+++ b/lisp/progmodes/cc-mode.el
@@ -1256,7 +1256,6 @@ Note that the style variables are always made local to 
the buffer."
       (re-search-forward "[\n\r]?\\(\\\\\\(.\\|\n\\)\\|[^\\\n\r]\\)*"
                         nil t)
       ;; We're at an EOLL or point-max.
-      (setq c-new-END (max c-new-END (min (1+ (point)) (point-max))))
       (if (equal (c-get-char-property (point) 'syntax-table) '(15))
          (if (memq (char-after) '(?\n ?\r))
              ;; Normally terminated invalid string.
@@ -1363,6 +1362,16 @@ Note that the style variables are always made local to 
the buffer."
                     (cdr (assq (char-before) c-string-innards-re-alist)) nil t)
                    (1+ (point)))))
           (cll)))
+        (end-hwm ; the highest position which could possibly be affected by
+                  ; insertion/deletion of string delimiters.
+         (max
+          (progn
+            (goto-char (min (1+ end)   ; 1+, in case a NL has become escaped.
+                            (point-max)))
+            (re-search-forward "\\(\\\\\\(.\\|\n\\|\r\\)\\|[^\\\n\r]\\)*"
+                               nil t)
+            (point))
+          c-new-END))
         s)
       (goto-char
        (cond ((null beg-literal-type)
@@ -1374,13 +1383,13 @@ Note that the style variables are always made local to 
the buffer."
       ;; Handle one string each time around the next while loop.
       (while
          (and
-          (< (point) c-new-END)
+          (< (point) end-hwm)
           (progn
             ;; Skip over any comments before the next string.
             (while (progn
-                     (setq s (parse-partial-sexp (point) c-new-END nil
+                     (setq s (parse-partial-sexp (point) end-hwm nil
                                                  nil s 'syntax-table))
-                     (and (< (point) c-new-END)
+                     (and (< (point) end-hwm)
                           (or (not (nth 3 s))
                               (not (memq (char-before) c-string-delims))))))
             ;; We're at the start of a string.