Speed up vertical-motion when screen coordinates are known

 src/indent.c (Fvertical_motion): Accept an additional argument
 CUR-COL and use it as the starting screen coordinate.
 src/window.c (window_scroll_line_based, Fmove_to_window_line): All
 callers of vertical-motion changed.

 doc/lispref/positions.texi (Screen Lines): Update the documentation of
 vertical-motion to document the new additional argument.

1 files changed, 11 insertions, 10 deletions

diff --git a/src/window.c b/src/window.c
index 293140041a9..d59616d0545 100644
--- a/src/window.c
+++ b/src/window.c
@@ -5350,14 +5350,14 @@ window_scroll_line_based (Lisp_Object window, int n, bool whole, int noerror)
 
   if (NILP (tem))
     {
-      Fvertical_motion (make_number (- (ht / 2)), window);
+      Fvertical_motion (make_number (- (ht / 2)), window, Qnil);
       startpos = PT;
       startbyte = PT_BYTE;
     }
 
   SET_PT_BOTH (startpos, startbyte);
   lose = n < 0 && PT == BEGV;
-  Fvertical_motion (make_number (n), window);
+  Fvertical_motion (make_number (n), window, Qnil);
   pos = PT;
   pos_byte = PT_BYTE;
   bolp = Fbolp ();
@@ -5389,7 +5389,7 @@ window_scroll_line_based (Lisp_Object window, int n, bool whole, int noerror)
           && (whole || !EQ (Vscroll_preserve_screen_position, Qt)))
         {
           SET_PT_BOTH (pos, pos_byte);
-          Fvertical_motion (original_pos, window);
+          Fvertical_motion (original_pos, window, Qnil);
         }
       /* If we scrolled forward, put point enough lines down
          that it is outside the scroll margin.  */
@@ -5400,7 +5400,7 @@ window_scroll_line_based (Lisp_Object window, int n, bool whole, int noerror)
           if (this_scroll_margin > 0)
             {
               SET_PT_BOTH (pos, pos_byte);
-              Fvertical_motion (make_number (this_scroll_margin), window);
+              Fvertical_motion (make_number (this_scroll_margin), window, Qnil);
               top_margin = PT;
             }
           else
@@ -5412,7 +5412,7 @@ window_scroll_line_based (Lisp_Object window, int n, bool whole, int noerror)
           else if (!NILP (Vscroll_preserve_screen_position))
             {
               SET_PT_BOTH (pos, pos_byte);
-              Fvertical_motion (original_pos, window);
+              Fvertical_motion (original_pos, window, Qnil);
             }
           else
             SET_PT (top_margin);
@@ -5424,7 +5424,8 @@ window_scroll_line_based (Lisp_Object window, int n, bool whole, int noerror)
           /* If we scrolled backward, put point near the end of the window
              but not within the scroll margin.  */
           SET_PT_BOTH (pos, pos_byte);
-          tem = Fvertical_motion (make_number (ht - this_scroll_margin), window);
+          tem = Fvertical_motion (make_number (ht - this_scroll_margin), window,
+                                  Qnil);
           if (XFASTINT (tem) == ht - this_scroll_margin)
             bottom_margin = PT;
           else
@@ -5438,10 +5439,10 @@ window_scroll_line_based (Lisp_Object window, int n, bool whole, int noerror)
               if (!NILP (Vscroll_preserve_screen_position))
                 {
                   SET_PT_BOTH (pos, pos_byte);
-                  Fvertical_motion (original_pos, window);
+                  Fvertical_motion (original_pos, window, Qnil);
                 }
               else
-                Fvertical_motion (make_number (-1), window);
+                Fvertical_motion (make_number (-1), window, Qnil);
             }
         }
     }
@@ -5999,7 +6000,7 @@ zero means top of window, negative means relative to bottom of window.  */)
   if (start < BEGV || start > ZV)
     {
       int height = window_internal_height (w);
-      Fvertical_motion (make_number (- (height / 2)), window);
+      Fvertical_motion (make_number (- (height / 2)), window, Qnil);
       set_marker_both (w->start, w->contents, PT, PT_BYTE);
       w->start_at_line_beg = !NILP (Fbolp ());
       w->force_start = 1;
@@ -6040,7 +6041,7 @@ zero means top of window, negative means relative to bottom of window.  */)
   if (w->vscroll)
     XSETINT (arg, XINT (arg) + 1);
 
-  return Fvertical_motion (arg, window);
+  return Fvertical_motion (arg, window, Qnil);
 }