patch 9.1.0891: building the completion list array is inefficient

Problem:  building the completion list array is inefficient
Solution: refactor and improve ins_compl_build_pum() func
          (glepnir)

current time complexity is O(n^2). I guess garray is not used here to save memory and avoid efficiency
is caused by heap memory allocation. A simple way is to add an extra pointer as a single linked list
to store the matching compl_T, and traverse this single linked list to generate compl_match_array.
The time complexity is O(n x m). The worst case is m=n, but we can still get a little improvement.
Because the if condition does not need to be run at one time. This should be a good solution for now.
Later we may be able to complete it in O(lgn) time. But this requires more reconstruction. So this is
the first step.

closes: #16125

Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

diff --git a/src/insexpand.c b/src/insexpand.c
index 6bc5075cbd84fff9db4fcf3406c9e03d59a4692b..ba5f919a9b765c699e4fa3b18f0be2d6e1660c78 100644 (file)
--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -95,6 +95,7 @@ struct compl_S
 {
     compl_T    *cp_next;
     compl_T    *cp_prev;
+    compl_T    *cp_match_next;         // matched next compl_T
     string_T   cp_str;                 // matched text
     char_u     *(cp_text[CPT_COUNT]);  // text for the menu
 #ifdef FEAT_EVAL
@@ -197,7 +198,7 @@ static int    compl_selected_item = -1;
 
 static int       *compl_fuzzy_scores;
 
-static int ins_compl_add(char_u *str, int len, char_u *fname, char_u **cptext, typval_T *user_data, int cdir, int flags, int adup, int *extra_hl);
+static int ins_compl_add(char_u *str, int len, char_u *fname, char_u **cptext, typval_T *user_data, int cdir, int flags, int adup, int *user_hl);
 static void ins_compl_longest_match(compl_T *match);
 static void ins_compl_del_pum(void);
 static void ins_compl_files(int count, char_u **files, int thesaurus, int flags, regmatch_T *regmatch, char_u *buf, int *dir);
@@ -754,7 +755,7 @@ ins_compl_add_infercase(
  *     cdir     - match direction. If 0, use "compl_direction".
  *     flags_arg - match flags (cp_flags)
  *     adup     - accept this match even if it is already present.
- *     *extra_hl - list of extra highlight attributes for abbr kind.
+ *     *user_hl  - list of extra highlight attributes for abbr kind.
  * If "cdir" is FORWARD, then the match is added after the current match.
  * Otherwise, it is added before the current match.
  *
@@ -772,7 +773,7 @@ ins_compl_add(
     int                cdir,
     int                flags_arg,
     int                adup,               // accept duplicate match
-    int                *extra_hl)          // user abbr/kind hlattr
+    int                *user_hl)           // user abbr/kind hlattr
 {
     compl_T    *match;
     int                dir = (cdir == 0 ? compl_direction : cdir);
@@ -838,8 +839,8 @@ ins_compl_add(
     else
        match->cp_fname = NULL;
     match->cp_flags = flags;
-    match->cp_user_abbr_hlattr = extra_hl ? extra_hl[0] : -1;
-    match->cp_user_kind_hlattr = extra_hl ? extra_hl[1] : -1;
+    match->cp_user_abbr_hlattr = user_hl ? user_hl[0] : -1;
+    match->cp_user_kind_hlattr = user_hl ? user_hl[1] : -1;
 
     if (cptext != NULL)
     {
@@ -1233,6 +1234,9 @@ ins_compl_build_pum(void)
     unsigned int cur_cot_flags = get_cot_flags();
     int                compl_no_select = (cur_cot_flags & COT_NOSELECT) != 0;
     int                compl_fuzzy_match = (cur_cot_flags & COT_FUZZY) != 0;
+    compl_T    *match_head = NULL;
+    compl_T    *match_tail = NULL;
+    compl_T    *match_next = NULL;
 
     // Need to build the popup menu list.
     compl_match_arraysize = 0;
@@ -1249,7 +1253,14 @@ ins_compl_build_pum(void)
                && (compl_leader.string == NULL
                    || ins_compl_equal(compl, compl_leader.string, (int)compl_leader.length)
                    || (compl_fuzzy_match && compl->cp_score > 0)))
+       {
            ++compl_match_arraysize;
+           if (match_head == NULL)
+               match_head = compl;
+           else
+               match_tail->cp_match_next  = compl;
+           match_tail = compl;
+       }
        compl = compl->cp_next;
     } while (compl != NULL && !is_first_match(compl));
 
@@ -1270,81 +1281,76 @@ ins_compl_build_pum(void)
            && shown_match_ok == FALSE)
        compl_shown_match = compl_no_select ? compl_first_match
                                            : compl_first_match->cp_next;
-
     i = 0;
-    compl = compl_first_match;
-    do
+    compl = match_head;
+    if (match_tail == match_head)
+       did_find_shown_match = TRUE;
+    while (compl != NULL)
     {
-       if (!match_at_original_text(compl)
-               && (compl_leader.string == NULL
-                   || ins_compl_equal(compl, compl_leader.string, (int)compl_leader.length)
-                   || (compl_fuzzy_match && compl->cp_score > 0)))
+       if (!shown_match_ok && !compl_fuzzy_match)
        {
-           if (!shown_match_ok && !compl_fuzzy_match)
+           if (compl == compl_shown_match || did_find_shown_match)
            {
-               if (compl == compl_shown_match || did_find_shown_match)
-               {
-                   // This item is the shown match or this is the
-                   // first displayed item after the shown match.
-                   compl_shown_match = compl;
-                   did_find_shown_match = TRUE;
-                   shown_match_ok = TRUE;
-               }
-               else
-                   // Remember this displayed match for when the
-                   // shown match is just below it.
-                   shown_compl = compl;
-               cur = i;
+               // This item is the shown match or this is the
+               // first displayed item after the shown match.
+               compl_shown_match = compl;
+               did_find_shown_match = TRUE;
+               shown_match_ok = TRUE;
            }
-           else if (compl_fuzzy_match)
+           else
+               // Remember this displayed match for when the
+               // shown match is just below it.
+               shown_compl = compl;
+           cur = i;
+       }
+       else if (compl_fuzzy_match)
+       {
+           if (i == 0)
+               shown_compl = compl;
+           // Update the maximum fuzzy score and the shown match
+           // if the current item's score is higher
+           if (compl->cp_score > max_fuzzy_score)
            {
-               if (i == 0)
-                   shown_compl = compl;
-               // Update the maximum fuzzy score and the shown match
-               // if the current item's score is higher
-               if (compl->cp_score > max_fuzzy_score)
-               {
-                   did_find_shown_match = TRUE;
-                   max_fuzzy_score = compl->cp_score;
-                   if (!compl_no_select)
-                       compl_shown_match = compl;
-               }
-
-               if (!shown_match_ok && compl == compl_shown_match && !compl_no_select)
-               {
-                   cur = i;
-                   shown_match_ok = TRUE;
-               }
+               did_find_shown_match = TRUE;
+               max_fuzzy_score = compl->cp_score;
+               if (!compl_no_select)
+                  compl_shown_match = compl;
+           }
 
-               // If there is no "no select" condition and the max fuzzy
-               // score is positive, or there is no completion leader or the
-               // leader length is zero, mark the shown match as valid and
-               // reset the current index.
-               if (!compl_no_select
-                       && (max_fuzzy_score > 0
-                               || (compl_leader.string == NULL || compl_leader.length == 0)))
-               {
-                   if (match_at_original_text(compl_shown_match))
-                     compl_shown_match = shown_compl;
-               }
+           if (!shown_match_ok && compl == compl_shown_match && !compl_no_select)
+           {
+               cur = i;
+               shown_match_ok = TRUE;
            }
 
-           if (compl->cp_text[CPT_ABBR] != NULL)
-               compl_match_array[i].pum_text = compl->cp_text[CPT_ABBR];
-           else
-               compl_match_array[i].pum_text = compl->cp_str.string;
-           compl_match_array[i].pum_kind = compl->cp_text[CPT_KIND];
-           compl_match_array[i].pum_info = compl->cp_text[CPT_INFO];
-           compl_match_array[i].pum_score = compl->cp_score;
-           compl_match_array[i].pum_user_abbr_hlattr = compl->cp_user_abbr_hlattr;
-           compl_match_array[i].pum_user_kind_hlattr = compl->cp_user_kind_hlattr;
-           if (compl->cp_text[CPT_MENU] != NULL)
-               compl_match_array[i++].pum_extra =
-                   compl->cp_text[CPT_MENU];
-           else
-               compl_match_array[i++].pum_extra = compl->cp_fname;
+           // If there is no "no select" condition and the max fuzzy
+           // score is positive, or there is no completion leader or the
+           // leader length is zero, mark the shown match as valid and
+           // reset the current index.
+           if (!compl_no_select
+                   && (max_fuzzy_score > 0
+                       || (compl_leader.string == NULL || compl_leader.length == 0)))
+           {
+               if (match_at_original_text(compl_shown_match))
+                   compl_shown_match = shown_compl;
+           }
        }
 
+       if (compl->cp_text[CPT_ABBR] != NULL)
+           compl_match_array[i].pum_text = compl->cp_text[CPT_ABBR];
+       else
+           compl_match_array[i].pum_text = compl->cp_str.string;
+       compl_match_array[i].pum_kind = compl->cp_text[CPT_KIND];
+       compl_match_array[i].pum_info = compl->cp_text[CPT_INFO];
+       compl_match_array[i].pum_score = compl->cp_score;
+       compl_match_array[i].pum_user_abbr_hlattr = compl->cp_user_abbr_hlattr;
+       compl_match_array[i].pum_user_kind_hlattr = compl->cp_user_kind_hlattr;
+       if (compl->cp_text[CPT_MENU] != NULL)
+           compl_match_array[i++].pum_extra =
+               compl->cp_text[CPT_MENU];
+       else
+           compl_match_array[i++].pum_extra = compl->cp_fname;
+
        if (compl == compl_shown_match && !compl_fuzzy_match)
        {
            did_find_shown_match = TRUE;
@@ -1362,8 +1368,10 @@ ins_compl_build_pum(void)
                shown_match_ok = TRUE;
            }
        }
-       compl = compl->cp_next;
-    } while (compl != NULL && !is_first_match(compl));
+       match_next = compl->cp_match_next;
+       compl->cp_match_next = NULL;
+       compl = match_next;
+    }
 
     if (compl_fuzzy_match && compl_leader.string != NULL && compl_leader.length > 0)
     {
@@ -2893,7 +2901,7 @@ ins_compl_add_tv(typval_T *tv, int dir, int fast)
     int                status;
     char_u     *user_abbr_hlname;
     char_u     *user_kind_hlname;
-    int                extra_hl[2] = { -1, -1 };
+    int                user_hl[2] = { -1, -1 };
 
     user_data.v_type = VAR_UNKNOWN;
     if (tv->v_type == VAR_DICT && tv->vval.v_dict != NULL)
@@ -2905,10 +2913,10 @@ ins_compl_add_tv(typval_T *tv, int dir, int fast)
        cptext[CPT_INFO] = dict_get_string(tv->vval.v_dict, "info", FALSE);
 
        user_abbr_hlname = dict_get_string(tv->vval.v_dict, "abbr_hlgroup", FALSE);
-       extra_hl[0] = get_user_highlight_attr(user_abbr_hlname);
+       user_hl[0] = get_user_highlight_attr(user_abbr_hlname);
 
        user_kind_hlname = dict_get_string(tv->vval.v_dict, "kind_hlgroup", FALSE);
-       extra_hl[1] = get_user_highlight_attr(user_kind_hlname);
+       user_hl[1] = get_user_highlight_attr(user_kind_hlname);
 
        dict_get_tv(tv->vval.v_dict, "user_data", &user_data);
        if (dict_get_string(tv->vval.v_dict, "icase", FALSE) != NULL
@@ -2933,7 +2941,7 @@ ins_compl_add_tv(typval_T *tv, int dir, int fast)
        return FAIL;
     }
     status = ins_compl_add(word, -1, NULL, cptext,
-                                    &user_data, dir, flags, dup, extra_hl);
+                                    &user_data, dir, flags, dup, user_hl);
     if (status != OK)
        clear_tv(&user_data);
     return status;

diff --git a/src/version.c b/src/version.c
index 243e348e9530fa26b0fb0899922f50dd6ffd2505..7edc79fb95f15e64d104b97c825bfbb984d97a0e 100644 (file)
--- a/src/version.c
+++ b/src/version.c
@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    891,
 /**/
     890,
 /**/