Introduce fast path for the widely used marker operation.

* alloc.c (build_marker): New function.
* lisp.h (build_marker): New prototype.
* buffer.c (clone_per_buffer_values, Fmake_indirect_buffer): Use it.
* composite.c (autocmp_chars): Likewise.
* editfns.c (buildmark): Remove.
(Fpoint_marker, Fpoint_min_marker, Fpoint_max_marker)
(save_restriction_save): Use build_marker.
* marker.c (buf_charpos_to_bytepos, buf_bytepos_to_charpos): Likewise.
* window.c (save_window_save): Likewise.

8 files changed, 67 insertions, 72 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index c8a9b3f8b0c..460bdaa198c 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,18 @@
 2012-07-06  Dmitry Antipov  <dmantipov@yandex.ru>
 
+        Introduce fast path for the widely used marker operation.
+        * alloc.c (build_marker): New function.
+        * lisp.h (build_marker): New prototype.
+        * buffer.c (clone_per_buffer_values, Fmake_indirect_buffer): Use it.
+        * composite.c (autocmp_chars): Likewise.
+        * editfns.c (buildmark): Remove.
+        (Fpoint_marker, Fpoint_min_marker, Fpoint_max_marker)
+        (save_restriction_save): Use build_marker.
+        * marker.c (buf_charpos_to_bytepos, buf_bytepos_to_charpos): Likewise.
+        * window.c (save_window_save): Likewise.
+
+2012-07-06  Dmitry Antipov  <dmantipov@yandex.ru>
+
         Do not use Fdelete_overlay in delete_all_overlays
         to avoid redundant calls to unchain_overlay.
         * buffer.c (drop_overlay): New function.
diff --git a/src/alloc.c b/src/alloc.c
index 695d71c6c94..88f96c41a15 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -3641,6 +3641,33 @@ DEFUN ("make-marker", Fmake_marker, Smake_marker, 0, 0, 0,
   return val;
 }
 
+/* Return a newly allocated marker which points into BUF
+   at character position CHARPOS and byte position BYTEPOS.  */
+
+Lisp_Object
+build_marker (struct buffer *buf, ptrdiff_t charpos, ptrdiff_t bytepos)
+{
+  Lisp_Object obj;
+  struct Lisp_Marker *m;
+
+  /* No dead buffers here.  */
+  eassert (!NILP (BVAR (buf, name)));
+
+  /* Every character is at least one byte.  */
+  eassert (charpos <= bytepos);
+
+  obj = allocate_misc ();
+  XMISCTYPE (obj) = Lisp_Misc_Marker;
+  m = XMARKER (obj);
+  m->buffer = buf;
+  m->charpos = charpos;
+  m->bytepos = bytepos;
+  m->insertion_type = 0;
+  m->next = BUF_MARKERS (buf);
+  BUF_MARKERS (buf) = m;
+  return obj;
+}
+
 /* Put MARKER back on the free list after using it temporarily.  */
 
 void
diff --git a/src/buffer.c b/src/buffer.c
index f73d2d07537..a37a61c0fc8 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -458,11 +458,8 @@ copy_overlays (struct buffer *b, struct Lisp_Overlay *list)
 static void
 clone_per_buffer_values (struct buffer *from, struct buffer *to)
 {
-  Lisp_Object to_buffer;
   int offset;
 
-  XSETBUFFER (to_buffer, to);
-
   for_each_per_buffer_object_at (offset)
     {
       Lisp_Object obj;
@@ -475,9 +472,9 @@ clone_per_buffer_values (struct buffer *from, struct buffer *to)
       if (MARKERP (obj) && XMARKER (obj)->buffer == from)
         {
           struct Lisp_Marker *m = XMARKER (obj);
-          obj = Fmake_marker ();
+
+          obj = build_marker (to, m->charpos, m->bytepos);
           XMARKER (obj)->insertion_type = m->insertion_type;
-          set_marker_both (obj, to_buffer, m->charpos, m->bytepos);
         }
 
       PER_BUFFER_VALUE (to, offset) = obj;
@@ -615,32 +612,24 @@ CLONE nil means the indirect buffer's state is reset to default values.  */)
       eassert (NILP (BVAR (b->base_buffer, begv_marker)));
       eassert (NILP (BVAR (b->base_buffer, zv_marker)));
 
-      BVAR (b->base_buffer, pt_marker) = Fmake_marker ();
-      set_marker_both (BVAR (b->base_buffer, pt_marker), base_buffer,
-                       b->base_buffer->pt,
-                       b->base_buffer->pt_byte);
+      BVAR (b->base_buffer, pt_marker) 
+        = build_marker (b->base_buffer, b->base_buffer->pt, b->base_buffer->pt_byte);
+
+      BVAR (b->base_buffer, begv_marker)
+        = build_marker (b->base_buffer, b->base_buffer->begv, b->base_buffer->begv_byte);
 
-      BVAR (b->base_buffer, begv_marker) = Fmake_marker ();
-      set_marker_both (BVAR (b->base_buffer, begv_marker), base_buffer,
-                       b->base_buffer->begv,
-                       b->base_buffer->begv_byte);
+      BVAR (b->base_buffer, zv_marker)
+        = build_marker (b->base_buffer, b->base_buffer->zv, b->base_buffer->zv_byte);
 
-      BVAR (b->base_buffer, zv_marker) = Fmake_marker ();
-      set_marker_both (BVAR (b->base_buffer, zv_marker), base_buffer,
-                       b->base_buffer->zv,
-                       b->base_buffer->zv_byte);
       XMARKER (BVAR (b->base_buffer, zv_marker))->insertion_type = 1;
     }
 
   if (NILP (clone))
     {
       /* Give the indirect buffer markers for its narrowing.  */
-      BVAR (b, pt_marker) = Fmake_marker ();
-      set_marker_both (BVAR (b, pt_marker), buf, b->pt, b->pt_byte);
-      BVAR (b, begv_marker) = Fmake_marker ();
-      set_marker_both (BVAR (b, begv_marker), buf, b->begv, b->begv_byte);
-      BVAR (b, zv_marker) = Fmake_marker ();
-      set_marker_both (BVAR (b, zv_marker), buf, b->zv, b->zv_byte);
+      BVAR (b, pt_marker) = build_marker (b, b->pt, b->pt_byte);
+      BVAR (b, begv_marker) = build_marker (b, b->begv, b->begv_byte);
+      BVAR (b, zv_marker) = build_marker (b, b->zv, b->zv_byte);
       XMARKER (BVAR (b, zv_marker))->insertion_type = 1;
     }
   else
diff --git a/src/composite.c b/src/composite.c
index 87fad6fa18f..bfc8093a87f 100644
--- a/src/composite.c
+++ b/src/composite.c
@@ -951,11 +951,8 @@ autocmp_chars (Lisp_Object rule, ptrdiff_t charpos, ptrdiff_t bytepos, ptrdiff_t
 
       /* Save point as marker before calling out to lisp.  */
       if (NILP (string))
-        {
-          Lisp_Object m = Fmake_marker ();
-          set_marker_both (m, Qnil, pt, pt_byte);
-          record_unwind_protect (restore_point_unwind, m);
-        }
+        record_unwind_protect (restore_point_unwind,
+                               build_marker (current_buffer, pt, pt_byte));
 
       args[0] = Vauto_composition_function;
       args[1] = AREF (rule, 2);
diff --git a/src/editfns.c b/src/editfns.c
index d4146cefb92..e40bea44e9c 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -205,15 +205,6 @@ DEFUN ("string-to-char", Fstring_to_char, Sstring_to_char, 1, 1, 0,
     XSETFASTINT (val, 0);
   return val;
 }
-
-static Lisp_Object
-buildmark (ptrdiff_t charpos, ptrdiff_t bytepos)
-{
-  register Lisp_Object mark;
-  mark = Fmake_marker ();
-  set_marker_both (mark, Qnil, charpos, bytepos);
-  return mark;
-}
 
 DEFUN ("point", Fpoint, Spoint, 0, 0, 0,
        doc: /* Return value of point, as an integer.
@@ -229,7 +220,7 @@ DEFUN ("point-marker", Fpoint_marker, Spoint_marker, 0, 0, 0,
        doc: /* Return value of point, as a marker object.  */)
   (void)
 {
-  return buildmark (PT, PT_BYTE);
+  return build_marker (current_buffer, PT, PT_BYTE);
 }
 
 DEFUN ("goto-char", Fgoto_char, Sgoto_char, 1, 1, "NGoto char: ",
@@ -1003,7 +994,7 @@ DEFUN ("point-min-marker", Fpoint_min_marker, Spoint_min_marker, 0, 0, 0,
 This is the beginning, unless narrowing (a buffer restriction) is in effect.  */)
   (void)
 {
-  return buildmark (BEGV, BEGV_BYTE);
+  return build_marker (current_buffer, BEGV, BEGV_BYTE);
 }
 
 DEFUN ("point-max", Fpoint_max, Spoint_max, 0, 0, 0,
@@ -1023,7 +1014,7 @@ This is (1+ (buffer-size)), unless narrowing (a buffer restriction)
 is in effect, in which case it is less.  */)
   (void)
 {
-  return buildmark (ZV, ZV_BYTE);
+  return build_marker (current_buffer, ZV, ZV_BYTE);
 }
 
 DEFUN ("gap-position", Fgap_position, Sgap_position, 0, 0, 0,
@@ -3289,8 +3280,8 @@ save_restriction_save (void)
     {
       Lisp_Object beg, end;
 
-      beg = buildmark (BEGV, BEGV_BYTE);
-      end = buildmark (ZV, ZV_BYTE);
+      beg = build_marker (current_buffer, BEGV, BEGV_BYTE);
+      end = build_marker (current_buffer, ZV, ZV_BYTE);
 
       /* END must move forward if text is inserted at its exact location.  */
       XMARKER (end)->insertion_type = 1;
diff --git a/src/lisp.h b/src/lisp.h
index 332ac298ce3..53a15545794 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -2853,6 +2853,7 @@ extern Lisp_Object set_marker_restricted (Lisp_Object, Lisp_Object, Lisp_Object)
 extern Lisp_Object set_marker_both (Lisp_Object, Lisp_Object, ptrdiff_t, ptrdiff_t);
 extern Lisp_Object set_marker_restricted_both (Lisp_Object, Lisp_Object,
                                                ptrdiff_t, ptrdiff_t);
+extern Lisp_Object build_marker (struct buffer *, ptrdiff_t, ptrdiff_t);
 extern void syms_of_marker (void);
 
 /* Defined in fileio.c */
diff --git a/src/marker.c b/src/marker.c
index a059987aa51..3b0adc7de8d 100644
--- a/src/marker.c
+++ b/src/marker.c
@@ -187,12 +187,7 @@ buf_charpos_to_bytepos (struct buffer *b, ptrdiff_t charpos)
          cache the correspondence by creating a marker here.
          It will last until the next GC.  */
       if (record)
-        {
-          Lisp_Object marker, buffer;
-          marker = Fmake_marker ();
-          XSETBUFFER (buffer, b);
-          set_marker_both (marker, buffer, best_below, best_below_byte);
-        }
+        build_marker (b, best_below, best_below_byte);
 
       if (byte_debug_flag)
         byte_char_debug_check (b, charpos, best_below_byte);
@@ -218,12 +213,7 @@ buf_charpos_to_bytepos (struct buffer *b, ptrdiff_t charpos)
          cache the correspondence by creating a marker here.
          It will last until the next GC.  */
       if (record)
-        {
-          Lisp_Object marker, buffer;
-          marker = Fmake_marker ();
-          XSETBUFFER (buffer, b);
-          set_marker_both (marker, buffer, best_above, best_above_byte);
-        }
+        build_marker (b, best_above, best_above_byte);
 
       if (byte_debug_flag)
         byte_char_debug_check (b, charpos, best_above_byte);
@@ -365,12 +355,7 @@ buf_bytepos_to_charpos (struct buffer *b, ptrdiff_t bytepos)
          But don't do it if BUF_MARKERS is nil;
          that is a signal from Fset_buffer_multibyte.  */
       if (record && BUF_MARKERS (b))
-        {
-          Lisp_Object marker, buffer;
-          marker = Fmake_marker ();
-          XSETBUFFER (buffer, b);
-          set_marker_both (marker, buffer, best_below, best_below_byte);
-        }
+        build_marker (b, best_below, best_below_byte);
 
       if (byte_debug_flag)
         byte_char_debug_check (b, best_below, bytepos);
@@ -398,12 +383,7 @@ buf_bytepos_to_charpos (struct buffer *b, ptrdiff_t bytepos)
          But don't do it if BUF_MARKERS is nil;
          that is a signal from Fset_buffer_multibyte.  */
       if (record && BUF_MARKERS (b))
-        {
-          Lisp_Object marker, buffer;
-          marker = Fmake_marker ();
-          XSETBUFFER (buffer, b);
-          set_marker_both (marker, buffer, best_above, best_above_byte);
-        }
+        build_marker (b, best_above, best_above_byte);
 
       if (byte_debug_flag)
         byte_char_debug_check (b, best_above, bytepos);
diff --git a/src/window.c b/src/window.c
index 0f88cbaece9..721b4d98477 100644
--- a/src/window.c
+++ b/src/window.c
@@ -5911,12 +5911,9 @@ save_window_save (Lisp_Object window, struct Lisp_Vector *vector, int i)
              is the selected window, then get the value of point from
              the buffer; pointm is garbage in the selected window.  */
           if (EQ (window, selected_window))
-            {
-              p->pointm = Fmake_marker ();
-              set_marker_both (p->pointm, w->buffer,
-                               BUF_PT (XBUFFER (w->buffer)),
-                               BUF_PT_BYTE (XBUFFER (w->buffer)));
-            }
+            p->pointm = build_marker (XBUFFER (w->buffer),
+                                      BUF_PT (XBUFFER (w->buffer)),
+                                      BUF_PT_BYTE (XBUFFER (w->buffer)));
           else
             p->pointm = Fcopy_marker (w->pointm, Qnil);
           XMARKER (p->pointm)->insertion_type