Refactor code that determines row->start and row->end.

 xdisp.c (find_row_end): New function, refactored from display_line.
 (display_line): Use it.

2 files changed, 129 insertions, 115 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index a6a89a4ea3b..13b2a29e74d 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2010-05-01  Eli Zaretskii  <eliz@gnu.org>
+
+        * xdisp.c (find_row_end): New function, refactored from display_line.
+        (display_line): Use it.
+
 2010-04-27  Eli Zaretskii  <eliz@gnu.org>
 
         * xdisp.c (set_cursor_from_row): Fix a crash when a display string
diff --git a/src/xdisp.c b/src/xdisp.c
index 9e14f7879a2..017aa690023 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -17370,6 +17370,123 @@ unproduce_glyphs (it, n)
     glyph[-n] = *glyph;
 }
 
+/* Find the positions in a bidi-reordered ROW to serve as ROW->start
+   and ROW->end.  */
+static struct display_pos
+find_row_end (it, row)
+     struct it *it;
+     struct glyph_row *row;
+{
+  /* FIXME: Revisit this when glyph ``spilling'' in continuation
+     lines' rows is implemented for bidi-reordered rows.  */
+  EMACS_INT min_pos = ZV + 1, max_pos = 0;
+  struct glyph *g;
+  struct it save_it;
+  struct text_pos tpos;
+  struct display_pos row_end = it->current;
+
+  for (g = row->glyphs[TEXT_AREA];
+       g < row->glyphs[TEXT_AREA] + row->used[TEXT_AREA];
+       g++)
+    {
+      if (BUFFERP (g->object))
+        {
+          if (g->charpos > 0 && g->charpos < min_pos)
+            min_pos = g->charpos;
+          if (g->charpos > max_pos)
+            max_pos = g->charpos;
+        }
+    }
+  /* Empty lines have a valid buffer position at their first
+     glyph, but that glyph's OBJECT is zero, as if it didn't come
+     from a buffer.  If we didn't find any valid buffer positions
+     in this row, maybe we have such an empty line.  */
+  if (max_pos == 0 && row->used[TEXT_AREA])
+    {
+      for (g = row->glyphs[TEXT_AREA];
+           g < row->glyphs[TEXT_AREA] + row->used[TEXT_AREA];
+           g++)
+        {
+          if (INTEGERP (g->object))
+            {
+              if (g->charpos > 0 && g->charpos < min_pos)
+                min_pos = g->charpos;
+              if (g->charpos > max_pos)
+                max_pos = g->charpos;
+            }
+        }
+    }
+
+  /* ROW->start is the value of min_pos, the minimal buffer position
+     we have in ROW.  */
+  if (min_pos <= ZV)
+    {
+      /* Avoid calling the costly CHAR_TO_BYTE if possible.  */
+      if (min_pos != row->start.pos.charpos)
+        SET_TEXT_POS (row->start.pos, min_pos, CHAR_TO_BYTE (min_pos));
+      if (max_pos == 0)
+        max_pos = min_pos;
+    }
+
+  /* For ROW->end, we need the position that is _after_ max_pos, in
+     the logical order, unless we are at ZV.  */
+  if (row->ends_at_zv_p)
+    {
+      if (!row->used[TEXT_AREA])
+        row->start.pos = row_end.pos;
+    }
+  else if (row->used[TEXT_AREA] && max_pos)
+    {
+      int at_eol_p;
+
+      SET_TEXT_POS (tpos, max_pos, CHAR_TO_BYTE (max_pos));
+      save_it = *it;
+      it->bidi_p = 0;
+      reseat (it, tpos, 0);
+      if (!get_next_display_element (it))
+        abort ();       /* this row cannot be at ZV, see above */
+      at_eol_p = ITERATOR_AT_END_OF_LINE_P (it);
+      set_iterator_to_next (it, 1);
+      row_end = it->current;
+      /* If the character at max_pos is not a newline and the
+         characters at max_pos+1 is a newline, skip that newline as
+         well.  Note that this may skip some invisible text.  */
+      if (!at_eol_p
+          && get_next_display_element (it)
+          && ITERATOR_AT_END_OF_LINE_P (it))
+        {
+          set_iterator_to_next (it, 1);
+          /* Record the position after the newline of a continued row.
+             We will need that to set ROW->end of the last row
+             produced for a continued line.  */
+          if (row->continued_p)
+            save_it.eol_pos = it->current.pos;
+          else
+            {
+              row_end = it->current;
+              save_it.eol_pos.charpos = save_it.eol_pos.bytepos = 0;
+            }
+        }
+      else if (!row->continued_p
+               && MATRIX_ROW_CONTINUATION_LINE_P (row)
+               && it->eol_pos.charpos > 0)
+        {
+          /* Last row of a continued line.  Use the position recorded
+             in IT->eol_pos, to the effect that the newline belongs to
+             this row, not to the row which displays the character
+             with the largest buffer position before the newline.  */
+          row_end.pos = it->eol_pos;
+          it->eol_pos.charpos = it->eol_pos.bytepos = 0;
+        }
+      *it = save_it;
+      /* The members of ROW->end that are not taken from buffer
+         positions are copied from IT->current.  */
+      row_end.string_pos = it->current.string_pos;
+      row_end.overlay_string_index = it->current.overlay_string_index;
+      row_end.dpvec_index = it->current.dpvec_index;
+    }
+  return row_end;
+}
 
 /* Construct the glyph row IT->glyph_row in the desired matrix of
    IT->w from text at the current position of IT.  See dispextern.h
@@ -17388,7 +17505,6 @@ display_line (it)
   int wrap_row_used = -1, wrap_row_ascent, wrap_row_height;
   int wrap_row_phys_ascent, wrap_row_phys_height;
   int wrap_row_extra_line_spacing;
-  struct display_pos row_end;
   int cvpos;
 
   /* We always start displaying at hpos zero even if hscrolled.  */
@@ -17912,120 +18028,13 @@ display_line (it)
   compute_line_metrics (it);
 
   /* Remember the position at which this line ends.  */
-  row->end = row_end = it->current;
+  row->end = it->current;
+  /* ROW->start and ROW->end must be the smallest and the largest
+     buffer positions in ROW.  But if ROW was bidi-reordered, these
+     two positions can be anywhere in the row, so we must rescan all
+     of the ROW's glyphs to find them.  */
   if (it->bidi_p)
-    {
-      /* ROW->start and ROW->end must be the smallest and largest
-         buffer positions in ROW.  But if ROW was bidi-reordered,
-         these two positions can be anywhere in the row, so we must
-         rescan all of the ROW's glyphs to find them.  */
-      /* FIXME: Revisit this when glyph ``spilling'' in continuation
-         lines' rows is implemented for bidi-reordered rows.  */
-      EMACS_INT min_pos = ZV + 1, max_pos = 0;
-      struct glyph *g;
-      struct it save_it;
-      struct text_pos tpos;
-
-      for (g = row->glyphs[TEXT_AREA];
-           g < row->glyphs[TEXT_AREA] + row->used[TEXT_AREA];
-           g++)
-        {
-          if (BUFFERP (g->object))
-            {
-              if (g->charpos > 0 && g->charpos < min_pos)
-                min_pos = g->charpos;
-              if (g->charpos > max_pos)
-                max_pos = g->charpos;
-            }
-        }
-      /* Empty lines have a valid buffer position at their first
-         glyph, but that glyph's OBJECT is zero, as if it didn't come
-         from a buffer.  If we didn't find any valid buffer positions
-         in this row, maybe we have such an empty line.  */
-      if (min_pos == ZV + 1 && row->used[TEXT_AREA])
-        {
-          for (g = row->glyphs[TEXT_AREA];
-               g < row->glyphs[TEXT_AREA] + row->used[TEXT_AREA];
-               g++)
-            {
-              if (INTEGERP (g->object))
-                {
-                  if (g->charpos > 0 && g->charpos < min_pos)
-                    min_pos = g->charpos;
-                  if (g->charpos > max_pos)
-                    max_pos = g->charpos;
-                }
-            }
-        }
-      if (min_pos <= ZV)
-        {
-          if (min_pos != row->start.pos.charpos)
-            {
-              row->start.pos.charpos = min_pos;
-              row->start.pos.bytepos = CHAR_TO_BYTE (min_pos);
-            }
-          if (max_pos == 0)
-            max_pos = min_pos;
-        }
-      /* For ROW->end, we need the position that is _after_ max_pos,
-         in the logical order, unless we are at ZV.  */
-      if (row->ends_at_zv_p)
-        {
-          if (!row->used[TEXT_AREA])
-            {
-              row->start.pos.charpos = row_end.pos.charpos;
-              row->start.pos.bytepos = row_end.pos.bytepos;
-            }
-        }
-      else if (row->used[TEXT_AREA] && max_pos)
-        {
-          SET_TEXT_POS (tpos, max_pos, CHAR_TO_BYTE (max_pos));
-          save_it = *it;
-          it->bidi_p = 0;
-          reseat (it, tpos, 0);
-          if (!get_next_display_element (it))
-            abort ();   /* row at ZV was already handled above */
-          set_iterator_to_next (it, 1);
-          row_end = it->current;
-          /* If the character at max_pos+1 is a newline, skip that as
-             well.  Note that this may skip some invisible text.  */
-          if (get_next_display_element (it)
-              && ITERATOR_AT_END_OF_LINE_P (it))
-            {
-              set_iterator_to_next (it, 1);
-              /* Record the position after the newline of a continued
-                 row.  We will need that to set ROW->end of the last
-                 row produced for a continued line.  */
-              if (row->continued_p)
-                {
-                  save_it.eol_pos.charpos = IT_CHARPOS (*it);
-                  save_it.eol_pos.bytepos = IT_BYTEPOS (*it);
-                }
-              else
-                {
-                  row_end = it->current;
-                  save_it.eol_pos.charpos = save_it.eol_pos.bytepos = 0;
-                }
-            }
-          else if (!row->continued_p
-                   && MATRIX_ROW_CONTINUATION_LINE_P (row)
-                   && it->eol_pos.charpos > 0)
-            {
-              /* Last row of a continued line.  Use the position
-                 recorded in ROW->eol_pos, to the effect that the
-                 newline belongs to this row, not to the row which
-                 displays the character with the largest buffer
-                 position.  */
-              row_end.pos = it->eol_pos;
-              it->eol_pos.charpos = it->eol_pos.bytepos = 0;
-            }
-          *it = save_it;
-          row_end.string_pos = it->current.string_pos;
-          row_end.overlay_string_index = it->current.overlay_string_index;
-          row_end.dpvec_index = it->current.dpvec_index;
-          row->end = row_end;
-        }
-    }
+    row->end = find_row_end (it, row);
 
   /* Record whether this row ends inside an ellipsis.  */
   row->ends_in_ellipsis_p
@@ -18079,7 +18088,7 @@ display_line (it)
      the flag accordingly.  */
   if (it->glyph_row < MATRIX_BOTTOM_TEXT_ROW (it->w->desired_matrix, it->w))
     it->glyph_row->reversed_p = row->reversed_p;
-  it->start = row_end;
+  it->start = row->end;
   return row->displays_text_p;
 }