Handle PHI nodes w/o a argument (PR ipa/80205).

2017-03-28  Martin Liska  <mliska@suse.cz>

	PR ipa/80205
	* g++.dg/ipa/pr80205.C: New test.
2017-03-28  Richard Biener  <rguenther@suse.de>

	PR ipa/80205
	* tree-inline.c (copy_phis_for_bb): Do not create PHI node
	without arguments, generate default definition of a SSA name.

From-SVN: r246530

gcc/ChangeLog

 2017-03-28  Richard Biener  <rguenther@suse.de>
 
+	PR ipa/80205
+	* tree-inline.c (copy_phis_for_bb): Do not create PHI node
+	without arguments, generate default definition of a SSA name.
+
+2017-03-28  Richard Biener  <rguenther@suse.de>
+
 	PR middle-end/80222
 	* gimple-fold.c (gimple_fold_indirect_ref): Do not touch
 	TYPE_REF_CAN_ALIAS_ALL references.

gcc/testsuite/ChangeLog

+2017-03-28  Martin Liska  <mliska@suse.cz>
+
+	PR ipa/80205
+	* g++.dg/ipa/pr80205.C: New test.
+
 2017-03-28  Senthil Kumar Selvaraj  <senthil_kumar.selvaraj@atmel.com>
 
 	* gcc.c-torture/execute/pr79121.c:Use __{U}INT32_TYPE__ for targets

gcc/testsuite/g++.dg/ipa/pr80205.C

+// PR ipa/80205
+// { dg-options "-fnon-call-exceptions --param early-inlining-insns=100 -O2" }
+
+class a
+{
+public:
+  virtual ~a ();
+};
+class b
+{
+public:
+  template <typename c> b (c);
+  ~b () { delete d; }
+  void
+  operator= (b e)
+  {
+    b (e).f (*this);
+  }
+  void
+  f (b &e)
+  {
+    a g;
+    d = e.d;
+    e.d = &g;
+  }
+  a *d;
+};
+void
+h ()
+{
+  b i = int();
+  void j ();
+  i = j;
+}

gcc/tree-inline.c

@@ -2344,18 +2344,26 @@ copy_phis_for_bb (basic_block bb, copy_body_data *id)
       if (!virtual_operand_p (res))
 	{
 	  walk_tree (&new_res, copy_tree_body_r, id, NULL);
+	  if (EDGE_COUNT (new_bb->preds) == 0)
+	    {
+	      /* Technically we'd want a SSA_DEFAULT_DEF here... */
+	      SSA_NAME_DEF_STMT (new_res) = gimple_build_nop ();
+	    }
+	  else
+	    {
 	      new_phi = create_phi_node (new_res, new_bb);
 	      FOR_EACH_EDGE (new_edge, ei, new_bb->preds)
 		{
-	      edge old_edge = find_edge ((basic_block) new_edge->src->aux, bb);
+		  edge old_edge = find_edge ((basic_block) new_edge->src->aux,
+					     bb);
 		  tree arg;
 		  tree new_arg;
 		  edge_iterator ei2;
 		  location_t locus;
 
-	      /* When doing partial cloning, we allow PHIs on the entry block
-		 as long as all the arguments are the same.  Find any input
-		 edge to see argument to copy.  */
+		  /* When doing partial cloning, we allow PHIs on the entry
+		     block as long as all the arguments are the same.
+		     Find any input edge to see argument to copy.  */
 		  if (!old_edge)
 		    FOR_EACH_EDGE (old_edge, ei2, bb->preds)
 		      if (!old_edge->src->aux)
@@ -2372,7 +2380,8 @@ copy_phis_for_bb (basic_block bb, copy_body_data *id)
 		      && !is_gimple_val (new_arg))
 		    {
 		      gimple_seq stmts = NULL;
-		  new_arg = force_gimple_operand (new_arg, &stmts, true, NULL);
+		      new_arg = force_gimple_operand (new_arg, &stmts, true,
+						      NULL);
 		      gsi_insert_seq_on_edge (new_edge, stmts);
 		      inserted = true;
 		    }
@@ -2391,6 +2400,7 @@ copy_phis_for_bb (basic_block bb, copy_body_data *id)
 		}
 	    }
 	}
+    }
 
   /* Commit the delayed edge insertions.  */
   if (inserted)