diff --git a/src/graph/graph.hh b/src/graph/graph.hh
index 7f38b9ca3..0d86ae672 100644
--- a/src/graph/graph.hh
+++ b/src/graph/graph.hh
@@ -762,14 +762,16 @@ struct graph_t
 
   void find_subgraph (unsigned node_idx, hb_set_t& subgraph)
   {
-    if (!subgraph.test_and_add (node_idx)) return;
+    if (subgraph.has (node_idx)) return;
+    subgraph.add (node_idx);
     for (const auto& link : vertices_[node_idx].obj.all_links ())
       find_subgraph (link.objidx, subgraph);
   }
 
   size_t find_subgraph_size (unsigned node_idx, hb_set_t& subgraph, unsigned max_depth = -1)
   {
-    if (!subgraph.test_and_add (node_idx)) return 0;
+    if (subgraph.has (node_idx)) return 0;
+    subgraph.add (node_idx);
 
     const auto& o = vertices_[node_idx].obj;
     size_t size = o.tail - o.head;
@@ -1157,7 +1159,8 @@ struct graph_t
     hb_set_t visited;
     for (unsigned p : vertices_[node_idx].parents)
     {
-      if (!visited.test_and_add (p)) continue;
+      if (visited.has (p)) continue;
+      visited.add (p);
 
       // Only real links can be wide
       for (const auto& l : vertices_[p].obj.real_links)
@@ -1361,10 +1364,14 @@ struct graph_t
                              hb_set_t& connected)
   {
     if (unlikely (!check_success (!visited.in_error ()))) return;
-    if (!visited.test_and_add (start_idx)) return;
+    if (visited.has (start_idx)) return;
+    visited.add (start_idx);
 
-    if (targets.test_and_del (start_idx))
+    if (targets.has (start_idx))
+    {
+      targets.del (start_idx);
       connected.add (start_idx);
+    }
 
     const auto& v = vertices_[start_idx];
 
diff --git a/src/hb-bit-page.hh b/src/hb-bit-page.hh
index a58150ff7..e1826e12a 100644
--- a/src/hb-bit-page.hh
+++ b/src/hb-bit-page.hh
@@ -115,31 +115,6 @@ struct hb_bit_page_t
   void set (hb_codepoint_t g, bool value) { if (value) add (g); else del (g); }
   bool get (hb_codepoint_t g) const { return elt (g) & mask (g); }
 
-  bool test_and_add (hb_codepoint_t g)
-  {
-    elt_t *e = &elt (g);
-    elt_t m = mask (g);
-
-    bool ret = !(*e & m);
-    if (ret)
-    {
-      *e |= m; dirty ();
-    }
-    return ret;
-  }
-  bool test_and_del (hb_codepoint_t g)
-  {
-    elt_t *e = &elt (g);
-    elt_t m = mask (g);
-
-    bool ret = *e & m;
-    if (ret)
-    {
-      *e &= ~m; dirty ();
-    }
-    return ret;
-  }
-
   void add_range (hb_codepoint_t a, hb_codepoint_t b)
   {
     elt_t *la = &elt (a);
diff --git a/src/hb-bit-set-invertible.hh b/src/hb-bit-set-invertible.hh
index 7cd6e7082..e765a479a 100644
--- a/src/hb-bit-set-invertible.hh
+++ b/src/hb-bit-set-invertible.hh
@@ -104,8 +104,6 @@ struct hb_bit_set_invertible_t
 
 
   void add (hb_codepoint_t g) { unlikely (inverted) ? s.del (g) : s.add (g); }
-  bool test_and_add (hb_codepoint_t g) { return unlikely (inverted) ? s.test_and_del (g) : s.test_and_add (g); }
-  bool test_and_del (hb_codepoint_t g) { return unlikely (inverted) ? s.test_and_add (g) : s.test_and_del (g); }
   bool add_range (hb_codepoint_t a, hb_codepoint_t b)
   { return unlikely (inverted) ? ((void) s.del_range (a, b), true) : s.add_range (a, b); }
 
diff --git a/src/hb-bit-set.hh b/src/hb-bit-set.hh
index de5c4ea70..17eb06541 100644
--- a/src/hb-bit-set.hh
+++ b/src/hb-bit-set.hh
@@ -154,22 +154,6 @@ struct hb_bit_set_t
     page_t *page = page_for (g, true); if (unlikely (!page)) return;
     page->add (g);
   }
-  bool test_and_add (hb_codepoint_t g)
-  {
-    if (unlikely (!successful)) return false;
-    if (unlikely (g == INVALID)) return false;
-    dirty ();
-    page_t *page = page_for (g, true); if (unlikely (!page)) return false;
-    return page->test_and_add (g);
-  }
-  bool test_and_del (hb_codepoint_t g)
-  {
-    if (unlikely (!successful)) return false;
-    if (unlikely (g == INVALID)) return false;
-    dirty ();
-    page_t *page = page_for (g); if (!page) return false;
-    return page->test_and_del (g);
-  }
   bool add_range (hb_codepoint_t a, hb_codepoint_t b)
   {
     if (unlikely (!successful)) return true; /* https://github.com/harfbuzz/harfbuzz/issues/657 */
diff --git a/src/hb-set.hh b/src/hb-set.hh
index 7a61de7c8..7d1c941e4 100644
--- a/src/hb-set.hh
+++ b/src/hb-set.hh
@@ -84,8 +84,6 @@ struct hb_sparseset_t
   uint32_t hash () const { return s.hash (); }
 
   void add (hb_codepoint_t g) { s.add (g); }
-  bool test_and_add (hb_codepoint_t g) { return s.test_and_add (g); }
-  bool test_and_del (hb_codepoint_t g) { return s.test_and_del (g); }
   bool add_range (hb_codepoint_t a, hb_codepoint_t b) { return s.add_range (a, b); }
 
   template <typename T>