diff --git a/autoload/airline/highlighter.vim b/autoload/airline/highlighter.vim
index 5e8a7851..c7327215 100644
--- a/autoload/airline/highlighter.vim
+++ b/autoload/airline/highlighter.vim
@@ -34,6 +34,10 @@ function! s:group_not_done(list, name)
   endif
 endfu
 
+function! s:separator_name(from, to, suffix)
+  return a:from.'_to_'.a:to.a:suffix
+endfu
+
 function! s:get_syn(group, what)
   if !exists("g:airline_gui_mode")
     let g:airline_gui_mode = airline#init#gui_mode()
@@ -178,7 +182,7 @@ function! s:exec_separator(dict, from, to, inverse, suffix)
   if pumvisible()
     return
   endif
-  let group = a:from.'_to_'.a:to.a:suffix
+  let group = s:separator_name(a:from, a:to, a:suffix)
   let l:from = airline#themes#get_highlight(a:from.a:suffix)
   let l:to = airline#themes#get_highlight(a:to.a:suffix)
   if a:inverse
@@ -290,9 +294,10 @@ function! airline#highlighter#highlight(modes, ...)
         " nothing to be done
         continue
       endif
-      " TODO: optimize this
       for sep in items(s:separators)
-        call <sid>exec_separator(dict, sep[1][0], sep[1][1], sep[1][2], suffix)
+        if s:group_not_done(airline_grouplist, s:separator_name(sep[1][0], sep[1][1], suffix))
+          call <sid>exec_separator(dict, sep[1][0], sep[1][1], sep[1][2], suffix)
+        endif
       endfor
     endif
   endfor