diff --git a/src/hb-buffer-private.hh b/src/hb-buffer-private.hh
index 42922223d..06d4912c7 100644
--- a/src/hb-buffer-private.hh
+++ b/src/hb-buffer-private.hh
@@ -131,6 +131,11 @@ struct _hb_buffer_t {
 			      unsigned int cluster_start,
 			      unsigned int cluster_end);
 
+  HB_INTERNAL void merge_clusters (unsigned int start,
+				   unsigned int end);
+  HB_INTERNAL void merge_out_clusters (unsigned int start,
+				       unsigned int end);
+
   /* Internal methods */
   HB_INTERNAL bool enlarge (unsigned int size);
 
diff --git a/src/hb-buffer.cc b/src/hb-buffer.cc
index e8bdfb1c6..6b562aac4 100644
--- a/src/hb-buffer.cc
+++ b/src/hb-buffer.cc
@@ -430,6 +430,29 @@ hb_buffer_t::reverse_clusters (void)
   reverse_range (start, i);
 }
 
+void
+hb_buffer_t::merge_clusters (unsigned int start,
+			     unsigned int end)
+{
+  unsigned int cluster = this->info[start].cluster;
+
+  for (unsigned int i = start + 1; i < end; i++)
+    cluster = MIN (cluster, this->info[i].cluster);
+  for (unsigned int i = start; i < end; i++)
+    this->info[i].cluster = cluster;
+}
+void
+hb_buffer_t::merge_out_clusters (unsigned int start,
+				 unsigned int end)
+{
+  unsigned int cluster = this->out_info[start].cluster;
+
+  for (unsigned int i = start + 1; i < end; i++)
+    cluster = MIN (cluster, this->out_info[i].cluster);
+  for (unsigned int i = start; i < end; i++)
+    this->out_info[i].cluster = cluster;
+}
+
 void
 hb_buffer_t::guess_properties (void)
 {
diff --git a/src/hb-ot-shape-complex-indic-machine.rl b/src/hb-ot-shape-complex-indic-machine.rl
index bcca6dab2..7af23c1b9 100644
--- a/src/hb-ot-shape-complex-indic-machine.rl
+++ b/src/hb-ot-shape-complex-indic-machine.rl
@@ -64,7 +64,7 @@ action found_vowel_syllable { found_vowel_syllable (map, buffer, mask_array, las
 action found_standalone_cluster { found_standalone_cluster (map, buffer, mask_array, last, p); }
 action found_non_indic { found_non_indic (map, buffer, mask_array, last, p); }
 
-action next_syllable { set_cluster (buffer, last, p); last = p; }
+action next_syllable { buffer->merge_clusters (last, p); last = p; }
 
 consonant_syllable =	(c.N? (z.H|H.z?))* c.N? A? (H.z? | matra_group*)? syllable_tail %(found_consonant_syllable);
 vowel_syllable =	(Ra H)? V N? (z.H.c | ZWJ.c)? matra_group* syllable_tail %(found_vowel_syllable);
@@ -83,18 +83,6 @@ main := (syllable %(next_syllable))**;
 }%%
 
 
-static void
-set_cluster (hb_buffer_t *buffer,
-	     unsigned int start, unsigned int end)
-{
-  unsigned int cluster = buffer->info[start].cluster;
-
-  for (unsigned int i = start + 1; i < end; i++)
-    cluster = MIN (cluster, buffer->info[i].cluster);
-  for (unsigned int i = start; i < end; i++)
-    buffer->info[i].cluster = cluster;
-}
-
 static void
 find_syllables (const hb_ot_map_t *map, hb_buffer_t *buffer, hb_mask_t *mask_array)
 {