diff --git a/mercurial/dirstate.py b/mercurial/dirstate.py
--- a/mercurial/dirstate.py
+++ b/mercurial/dirstate.py
@@ -49,6 +49,11 @@ def _getfsnow(vfs):
         os.close(tmpfd)
         vfs.unlink(tmpname)
 
+def nonnormalentries(dmap):
+    '''Compute the nonnormal dirstate entries from the dmap'''
+    return set(fname for fname, e in dmap.iteritems()
+           if e[0] != 'n' or e[3] == -1)
+
 def _trypending(root, vfs, filename):
     '''Open  file to be read according to HG_PENDING environment variable