vim-patch:8.1.0469: too often indexing in qf_lists[]

Problem:    Too often indexing in qf_lists[].
Solution:   Use a qf_list_T pointer. (Yegappan Lakshmanan)
https://github.com/vim/vim/commit/108e7b422b7b59153dd5af1fb75e83fa36ff3db4

2 files changed, 65 insertions, 50 deletions

diff --git a/src/nvim/quickfix.c b/src/nvim/quickfix.c
index 56f6f8b91b..6ac7f374ea 100644
--- a/src/nvim/quickfix.c
+++ b/src/nvim/quickfix.c
@@ -383,7 +383,7 @@ static char_u * scanf_fmt_to_regpat(
 
 // Analyze/parse an errorformat prefix.
 static const char_u *efm_analyze_prefix(const char_u *efmp, efm_T *efminfo,
-                                  char_u *errmsg, size_t errmsglen)
+                                        char_u *errmsg, size_t errmsglen)
   FUNC_ATTR_NONNULL_ALL
 {
   if (vim_strchr((char_u *)"+-", *efmp) != NULL) {
@@ -1138,7 +1138,7 @@ qf_init_ext(
 error2:
   if (!adding) {
     // Error when creating a new list. Free the new list
-    qf_free(&qi->qf_lists[qi->qf_curlist]);
+    qf_free(qfl);
     qi->qf_listcount--;
     if (qi->qf_curlist > 0) {
       qi->qf_curlist--;
@@ -1189,6 +1189,7 @@ static char_u * qf_cmdtitle(char_u *cmd)
 static void qf_new_list(qf_info_T *qi, const char_u *qf_title)
 {
   int i;
+  qf_list_T *qfl;
 
   // If the current entry is not the last entry, delete entries beyond
   // the current entry.  This makes it possible to browse in a tree-like
@@ -1209,9 +1210,10 @@ static void qf_new_list(qf_info_T *qi, const char_u *qf_title)
     qi->qf_curlist = LISTCOUNT - 1;
   } else
     qi->qf_curlist = qi->qf_listcount++;
-  memset(&qi->qf_lists[qi->qf_curlist], 0, (size_t)(sizeof(qf_list_T)));
-  qf_store_title(&qi->qf_lists[qi->qf_curlist], qf_title);
-  qi->qf_lists[qi->qf_curlist].qf_id = ++last_qf_id;
+  qfl = &qi->qf_lists[qi->qf_curlist];
+  memset(qfl, 0, (size_t)(sizeof(qf_list_T)));
+  qf_store_title(qfl, qf_title);
+  qfl->qf_id = ++last_qf_id;
 }
 
 // Parse the match for filename ('%f') pattern in regmatch.
@@ -1917,6 +1919,7 @@ void copy_loclist_stack(win_T *from, win_T *to)
 static int qf_get_fnum(qf_info_T *qi, int qf_idx, char_u *directory,
                        char_u *fname)
 {
+  qf_list_T *qfl = &qi->qf_lists[qf_idx];
   char_u *ptr = NULL;
   char_u *bufname;
   buf_T *buf;
@@ -1938,7 +1941,7 @@ static int qf_get_fnum(qf_info_T *qi, int qf_idx, char_u *directory,
     // directory change.
     if (!os_path_exists(ptr)) {
       xfree(ptr);
-      directory = qf_guess_filepath(&qi->qf_lists[qf_idx], fname);
+      directory = qf_guess_filepath(qfl, fname);
       if (directory) {
         ptr = (char_u *)concat_fnames((char *)directory, (char *)fname, true);
       } else {
@@ -3268,6 +3271,7 @@ void qf_view_result(bool split)
 void ex_cwindow(exarg_T *eap)
 {
   qf_info_T   *qi = &ql_info;
+  qf_list_T   *qfl;
   win_T       *win;
 
   if (is_loclist_cmd(eap->cmdidx)) {
@@ -3276,6 +3280,8 @@ void ex_cwindow(exarg_T *eap)
       return;
   }
 
+  qfl = &qi->qf_lists[qi->qf_curlist];
+
   /* Look for an existing quickfix window.  */
   win = qf_find_win(qi);
 
@@ -3285,7 +3291,7 @@ void ex_cwindow(exarg_T *eap)
    * it if we have errors; otherwise, leave it closed.
    */
   if (qf_stack_empty(qi)
-      || qi->qf_lists[qi->qf_curlist].qf_nonevalid
+      || qfl->qf_nonevalid
       || qf_list_empty(qi, qi->qf_curlist)) {
     if (win != NULL) {
       ex_cclose(eap);
@@ -3424,6 +3430,7 @@ static void qf_set_title_var(qf_list_T *qfl)
 void ex_copen(exarg_T *eap)
 {
   qf_info_T   *qi = &ql_info;
+  qf_list_T   *qfl;
   int height;
   int status = FAIL;
 
@@ -3454,12 +3461,13 @@ void ex_copen(exarg_T *eap)
     }
   }
 
-  qf_set_title_var(&qi->qf_lists[qi->qf_curlist]);
+  qfl = &qi->qf_lists[qi->qf_curlist];
+  qf_set_title_var(qfl);
 
   // Fill the buffer with the quickfix list.
   qf_fill_buffer(qi, curbuf, NULL);
 
-  curwin->w_cursor.lnum = qi->qf_lists[qi->qf_curlist].qf_index;
+  curwin->w_cursor.lnum = qfl->qf_index;
   curwin->w_cursor.col = 0;
   check_cursor();
   update_topline();             // scroll to show the line
@@ -3746,13 +3754,14 @@ static void qf_fill_buffer(qf_info_T *qi, buf_T *buf, qfline_T *old_last)
 
   // Check if there is anything to display
   if (!qf_stack_empty(qi)) {
+     qf_list_T *qfl = &qi->qf_lists[qi->qf_curlist];
      char_u dirname[MAXPATHL];
 
      *dirname = NUL;
 
     // Add one line for each error
     if (old_last == NULL) {
-      qfp = qi->qf_lists[qi->qf_curlist].qf_start;
+      qfp = qfl->qf_start;
       lnum = 0;
     } else {
       qfp = old_last->qf_next;
@@ -3801,9 +3810,9 @@ static void qf_fill_buffer(qf_info_T *qi, buf_T *buf, qfline_T *old_last)
   KeyTyped = old_KeyTyped;
 }
 
-static void qf_list_changed(qf_info_T *qi, int qf_idx)
+static void qf_list_changed(qf_list_T *qfl)
 {
-    qi->qf_lists[qf_idx].qf_changedtick++;
+    qfl->qf_changedtick++;
 }
 
 /// Return the quickfix/location list number with the given identifier.
@@ -3967,7 +3976,7 @@ void ex_make(exarg_T *eap)
     }
   }
   if (res >= 0) {
-    qf_list_changed(qi, qi->qf_curlist);
+    qf_list_changed(&qi->qf_lists[qi->qf_curlist]);
   }
   // Remember the current quickfix list identifier, so that we can
   // check for autocommands changing the current quickfix list.
@@ -4040,6 +4049,7 @@ size_t qf_get_size(exarg_T *eap)
   FUNC_ATTR_NONNULL_ALL
 {
   qf_info_T *qi = &ql_info;
+  qf_list_T *qfl;
   if (is_loclist_cmd(eap->cmdidx)) {
     // Location list.
     qi = GET_LOC_LIST(curwin);
@@ -4053,8 +4063,8 @@ size_t qf_get_size(exarg_T *eap)
   qfline_T *qfp;
   size_t i;
   assert(qi->qf_lists[qi->qf_curlist].qf_count >= 0);
-  for (i = 0, qfp = qi->qf_lists[qi->qf_curlist].qf_start;
-       i < (size_t)qi->qf_lists[qi->qf_curlist].qf_count && qfp != NULL;
+  qfl = &qi->qf_lists[qi->qf_curlist];
+  for (i = 0, qfp = qfl->qf_start; i < (size_t)qfl->qf_count && qfp != NULL;
        i++, qfp = qfp->qf_next) {
     if (!qfp->qf_valid) {
       continue;
@@ -4353,7 +4363,7 @@ void ex_cfile(exarg_T *eap)
     }
   }
   if (res >= 0) {
-    qf_list_changed(qi, qi->qf_curlist);
+    qf_list_changed(&qi->qf_lists[qi->qf_curlist]);
   }
   unsigned save_qfid = qi->qf_lists[qi->qf_curlist].qf_id;
   if (au_name != NULL) {
@@ -4564,6 +4574,7 @@ void ex_vimgrep(exarg_T *eap)
   char_u      *p;
   int fi;
   qf_info_T   *qi = &ql_info;
+  qf_list_T   *qfl;
   win_T *wp = NULL;
   buf_T       *buf;
   int duplicate_name = FALSE;
@@ -4741,10 +4752,11 @@ void ex_vimgrep(exarg_T *eap)
 
   FreeWild(fcount, fnames);
 
-  qi->qf_lists[qi->qf_curlist].qf_nonevalid = FALSE;
-  qi->qf_lists[qi->qf_curlist].qf_ptr = qi->qf_lists[qi->qf_curlist].qf_start;
-  qi->qf_lists[qi->qf_curlist].qf_index = 1;
-  qf_list_changed(qi, qi->qf_curlist);
+  qfl = &qi->qf_lists[qi->qf_curlist];
+  qfl->qf_nonevalid = false;
+  qfl->qf_ptr = qfl->qf_start;
+  qfl->qf_index = 1;
+  qf_list_changed(qfl);
 
   qf_update_buffer(qi, NULL);
 
@@ -5228,10 +5240,10 @@ static int qf_getprop_defaults(qf_info_T *qi, int flags, dict_T *retdict)
 }
 
 /// Return the quickfix list title as 'title' in retdict
-static int qf_getprop_title(qf_info_T *qi, int qf_idx, dict_T *retdict)
+static int qf_getprop_title(qf_list_T *qfl, dict_T *retdict)
 {
     return tv_dict_add_str(retdict, S_LEN("title"),
-                           (const char *)qi->qf_lists[qf_idx].qf_title);
+                           (const char *)qfl->qf_title);
 }
 
 // Returns the identifier of the window used to display files from a location
@@ -5264,13 +5276,13 @@ static int qf_getprop_items(qf_info_T *qi, int qf_idx, dict_T *retdict)
 }
 
 /// Return the quickfix list context (if any) as 'context' in retdict.
-static int qf_getprop_ctx(qf_info_T *qi, int qf_idx, dict_T *retdict)
+static int qf_getprop_ctx(qf_list_T *qfl, dict_T *retdict)
 {
   int status;
 
-  if (qi->qf_lists[qf_idx].qf_ctx != NULL) {
+  if (qfl->qf_ctx != NULL) {
     dictitem_T *di = tv_dict_item_alloc_len(S_LEN("context"));
-    tv_copy(qi->qf_lists[qf_idx].qf_ctx, &di->di_tv);
+    tv_copy(qfl->qf_ctx, &di->di_tv);
     status = tv_dict_add(retdict, di);
     if (status == FAIL) {
       tv_dict_item_free(di);
@@ -5282,15 +5294,15 @@ static int qf_getprop_ctx(qf_info_T *qi, int qf_idx, dict_T *retdict)
   return status;
 }
 
-/// Return the quickfix list index as 'idx' in retdict
+/// Return the current quickfix list index as 'idx' in retdict
 static int qf_getprop_idx(qf_info_T *qi, int qf_idx, dict_T *retdict)
 {
-  int idx = qi->qf_lists[qf_idx].qf_index;
+  int curidx = qi->qf_lists[qf_idx].qf_index;
   if (qf_list_empty(qi, qf_idx)) {
-    // For empty lists, qf_index is set to 1
-    idx = 0;
+    // For empty lists, current index is set to 0
+    curidx = 0;
   }
-  return tv_dict_add_nr(retdict, S_LEN("idx"), idx);
+  return tv_dict_add_nr(retdict, S_LEN("idx"), curidx);
 }
 
 /// Return quickfix/location list details (title) as a dictionary.
@@ -5302,7 +5314,7 @@ int qf_get_properties(win_T *wp, dict_T *what, dict_T *retdict)
   qf_list_T *qfl;
   dictitem_T *di = NULL;
   int status = OK;
-  int qf_idx;
+  int qf_idx = INVALID_QFIDX;
 
   if ((di = tv_dict_find(what, S_LEN("lines"))) != NULL) {
     return qf_get_list_from_lines(what, di, retdict);
@@ -5326,7 +5338,7 @@ int qf_get_properties(win_T *wp, dict_T *what, dict_T *retdict)
   qfl = &qi->qf_lists[qf_idx];
 
   if (flags & QF_GETLIST_TITLE) {
-    status = qf_getprop_title(qi, qf_idx, retdict);
+    status = qf_getprop_title(qfl, retdict);
   }
   if ((status == OK) && (flags & QF_GETLIST_NR)) {
     status = tv_dict_add_nr(retdict, S_LEN("nr"), qf_idx + 1);
@@ -5338,7 +5350,7 @@ int qf_get_properties(win_T *wp, dict_T *what, dict_T *retdict)
     status = qf_getprop_items(qi, qf_idx, retdict);
   }
   if ((status == OK) && (flags & QF_GETLIST_CONTEXT)) {
-    status = qf_getprop_ctx(qi, qf_idx, retdict);
+    status = qf_getprop_ctx(qfl, retdict);
   }
   if ((status == OK) && (flags & QF_GETLIST_ID)) {
     status = tv_dict_add_nr(retdict, S_LEN("id"), qfl->qf_id);
@@ -5551,13 +5563,13 @@ static int qf_setprop_title(qf_info_T *qi, int qf_idx, const dict_T *what,
                             const dictitem_T *di)
   FUNC_ATTR_NONNULL_ALL
 {
+  qf_list_T *qfl = &qi->qf_lists[qf_idx];
   if (di->di_tv.v_type != VAR_STRING) {
     return FAIL;
   }
 
-  xfree(qi->qf_lists[qf_idx].qf_title);
-  qi->qf_lists[qf_idx].qf_title =
-    (char_u *)tv_dict_get_string(what, "title", true);
+  xfree(qfl->qf_title);
+  qfl->qf_title = (char_u *)tv_dict_get_string(what, "title", true);
   if (qf_idx == qi->qf_curlist) {
     qf_update_win_titlevar(qi);
   }
@@ -5640,6 +5652,7 @@ static int qf_set_properties(qf_info_T *qi, const dict_T *what, int action,
                              char_u *title)
   FUNC_ATTR_NONNULL_ALL
 {
+  qf_list_T *qfl;
   dictitem_T *di;
   int  retval = FAIL;
   bool newlist = action == ' ' || qf_stack_empty(qi);
@@ -5654,6 +5667,7 @@ static int qf_set_properties(qf_info_T *qi, const dict_T *what, int action,
     qf_idx = qi->qf_curlist;
   }
 
+  qfl = &qi->qf_lists[qf_idx];
   if ((di = tv_dict_find(what, S_LEN("title"))) != NULL) {
     retval = qf_setprop_title(qi, qf_idx, what, di);
   }
@@ -5664,18 +5678,18 @@ static int qf_set_properties(qf_info_T *qi, const dict_T *what, int action,
     retval = qf_setprop_items_from_lines(qi, qf_idx, what, di, action);
   }
   if ((di = tv_dict_find(what, S_LEN("context"))) != NULL) {
-    retval = qf_setprop_context(&qi->qf_lists[qf_idx], di);
+    retval = qf_setprop_context(qfl, di);
   }
 
   if (retval == OK) {
-    qf_list_changed(qi, qf_idx);
+    qf_list_changed(qfl);
   }
 
   return retval;
 }
 
-// Find the non-location list window with the specified location list in the
-// current tabpage.
+// Find the non-location list window with the specified location list stack in
+// the current tabpage.
 static win_T * find_win_with_ll(qf_info_T *qi)
 {
   FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
@@ -5754,7 +5768,7 @@ int set_errorlist(win_T *wp, list_T *list, int action, char_u *title,
   } else {
     retval = qf_add_entries(qi, qi->qf_curlist, list, title, action);
     if (retval == OK) {
-      qf_list_changed(qi, qi->qf_curlist);
+      qf_list_changed(&qi->qf_lists[qi->qf_curlist]);
     }
   }
 
@@ -5889,7 +5903,7 @@ void ex_cbuffer(exarg_T *eap)
                              && eap->cmdidx != CMD_laddbuffer),
                             eap->line1, eap->line2, qf_title, NULL);
       if (res >= 0) {
-        qf_list_changed(qi, qi->qf_curlist);
+        qf_list_changed(&qi->qf_lists[qi->qf_curlist]);
       }
       // Remember the current quickfix list identifier, so that we can
       // check for autocommands changing the current quickfix list.
@@ -5971,7 +5985,7 @@ void ex_cexpr(exarg_T *eap)
                             (linenr_T)0, (linenr_T)0,
                             qf_cmdtitle(*eap->cmdlinep), NULL);
       if (res >= 0) {
-        qf_list_changed(qi, qi->qf_curlist);
+        qf_list_changed(&qi->qf_lists[qi->qf_curlist]);
       }
       // Remember the current quickfix list identifier, so that we can
       // check for autocommands changing the current quickfix list.
@@ -6171,10 +6185,12 @@ void ex_helpgrep(exarg_T *eap)
 
     vim_regfree(regmatch.regprog);
 
-    qi->qf_lists[qi->qf_curlist].qf_nonevalid = FALSE;
-    qi->qf_lists[qi->qf_curlist].qf_ptr =
-      qi->qf_lists[qi->qf_curlist].qf_start;
-    qi->qf_lists[qi->qf_curlist].qf_index = 1;
+    qf_list_T *qfl = &qi->qf_lists[qi->qf_curlist];
+    qfl->qf_nonevalid = false;
+    qfl->qf_ptr = qfl->qf_start;
+    qfl->qf_index = 1;
+    qf_list_changed(qfl);
+    qf_update_buffer(qi, NULL);
   }
 
   if (p_cpo == empty_option) {
@@ -6184,9 +6200,6 @@ void ex_helpgrep(exarg_T *eap)
     free_string_option(save_cpo);
   }
 
-  qf_list_changed(qi, qi->qf_curlist);
-  qf_update_buffer(qi, NULL);
-
   if (au_name != NULL) {
     apply_autocmds(EVENT_QUICKFIXCMDPOST, au_name,
                    curbuf->b_fname, true, curbuf);
diff --git a/src/nvim/testdir/test_quickfix.vim b/src/nvim/testdir/test_quickfix.vim
index c0f39884ea..a5ce41d8d2 100644
--- a/src/nvim/testdir/test_quickfix.vim
+++ b/src/nvim/testdir/test_quickfix.vim
@@ -540,6 +540,8 @@ func s:test_xhelpgrep(cchar)
 
   " Search for non existing help string
   call assert_fails('Xhelpgrep a1b2c3', 'E480:')
+  " Invalid regular expression
+  call assert_fails('Xhelpgrep \@<!', 'E480:')
 endfunc
 
 func Test_helpgrep()