diff --git a/gcc/rtl-ssa.h b/gcc/rtl-ssa.h
index f0cf656f5ac..17337639ae8 100644
--- a/gcc/rtl-ssa.h
+++ b/gcc/rtl-ssa.h
@@ -50,6 +50,7 @@
 #include "mux-utils.h"
 #include "rtlanal.h"
 #include "cfgbuild.h"
+#include "hash-set.h"
 
 // Provides the global crtl->ssa.
 #include "memmodel.h"
diff --git a/gcc/rtl-ssa/changes.cc b/gcc/rtl-ssa/changes.cc
index ce51d6ccd8d..6119ec3535b 100644
--- a/gcc/rtl-ssa/changes.cc
+++ b/gcc/rtl-ssa/changes.cc
@@ -429,7 +429,8 @@ update_insn_in_place (insn_change &change)
 // POS gives the final position of INSN, which hasn't yet been moved into
 // place.
 void
-function_info::finalize_new_accesses (insn_change &change, insn_info *pos)
+function_info::finalize_new_accesses (insn_change &change, insn_info *pos,
+				      hash_set<def_info *> &new_sets)
 {
   insn_info *insn = change.insn ();
 
@@ -465,6 +466,12 @@ function_info::finalize_new_accesses (insn_change &change, insn_info *pos)
 		// later in case we see a second write to the same resource.
 		def_info *perm_def = allocate<set_info> (change.insn (),
 							 def->resource ());
+
+		// Keep track of the new set so we remember to add it to the
+		// def chain later.
+		if (new_sets.add (perm_def))
+		  gcc_unreachable (); // We shouldn't see duplicates here.
+
 		def->set_last_def (perm_def);
 		def = perm_def;
 	      }
@@ -647,7 +654,8 @@ function_info::finalize_new_accesses (insn_change &change, insn_info *pos)
 // Copy information from CHANGE to its underlying insn_info, given that
 // the insn_info has already been placed appropriately.
 void
-function_info::apply_changes_to_insn (insn_change &change)
+function_info::apply_changes_to_insn (insn_change &change,
+				      hash_set<def_info *> &new_sets)
 {
   insn_info *insn = change.insn ();
   if (change.is_deletion ())
@@ -659,10 +667,11 @@ function_info::apply_changes_to_insn (insn_change &change)
   // Copy the cost.
   insn->set_cost (change.new_cost);
 
-  // Add all clobbers.  Sets and call clobbers never move relative to
-  // other definitions, so are OK as-is.
+  // Add all clobbers and newly-created sets.  Existing sets and call
+  // clobbers never move relative to other definitions, so are OK as-is.
   for (def_info *def : change.new_defs)
-    if (is_a<clobber_info *> (def) && !def->is_call_clobber ())
+    if ((is_a<clobber_info *> (def) && !def->is_call_clobber ())
+	|| (is_a<set_info *> (def) && new_sets.contains (def)))
       add_def (def);
 
   // Add all uses, now that their position is final.
@@ -793,6 +802,10 @@ function_info::change_insns (array_slice<insn_change *> changes)
       placeholders[i] = placeholder;
     }
 
+  // We need to keep track of newly-added sets as these need adding to
+  // the def chain later.
+  hash_set<def_info *> new_sets;
+
   // Finalize the new list of accesses for each change.  Don't install them yet,
   // so that we still have access to the old lists below.
   //
@@ -806,7 +819,8 @@ function_info::change_insns (array_slice<insn_change *> changes)
       insn_info *placeholder = placeholders[i];
       if (!change.is_deletion ())
 	finalize_new_accesses (change,
-			       placeholder ? placeholder : change.insn ());
+			       placeholder ? placeholder : change.insn (),
+			       new_sets);
     }
 
   // Remove all definitions that are no longer needed.  After the above,
@@ -861,7 +875,7 @@ function_info::change_insns (array_slice<insn_change *> changes)
 
   // Apply the changes to the underlying insn_infos.
   for (insn_change *change : changes)
-    apply_changes_to_insn (*change);
+    apply_changes_to_insn (*change, new_sets);
 
   // Now that the insns and accesses are up to date, add any REG_UNUSED notes.
   for (insn_change *change : changes)
diff --git a/gcc/rtl-ssa/functions.h b/gcc/rtl-ssa/functions.h
index 962180e27d6..4573453d896 100644
--- a/gcc/rtl-ssa/functions.h
+++ b/gcc/rtl-ssa/functions.h
@@ -299,8 +299,10 @@ private:
   void process_uses_of_deleted_def (set_info *);
   insn_info *add_placeholder_after (insn_info *);
   void possibly_queue_changes (insn_change &);
-  void finalize_new_accesses (insn_change &, insn_info *);
-  void apply_changes_to_insn (insn_change &);
+  void finalize_new_accesses (insn_change &, insn_info *,
+			      hash_set<def_info *> &);
+  void apply_changes_to_insn (insn_change &,
+			      hash_set<def_info *> &);
 
   void init_function_data ();
   void calculate_potential_phi_regs (build_info &);