gcc/gcc48-pr56265.patch

2013-02-20  Jan Hubicka  <jh@suse.cz>

	PR tree-optimization/56265
	* ipa-prop.c (ipa_make_edge_direct_to_target): Fixup callgraph when target is
	referenced for firs ttime.

	* testsuite/g++.dg/ipa/devirt-11.C: New testcase.

--- gcc/ipa-prop.c	(revision 196176)
+++ gcc/ipa-prop.c	(revision 196177)
@@ -2100,10 +2100,65 @@ ipa_make_edge_direct_to_target (struct c
   if (TREE_CODE (target) == ADDR_EXPR)
     target = TREE_OPERAND (target, 0);
   if (TREE_CODE (target) != FUNCTION_DECL)
-    return NULL;
+    {
+      target = canonicalize_constructor_val (target, NULL);
+      if (!target || TREE_CODE (target) != FUNCTION_DECL)
+	{
+	  if (dump_file)
+	    fprintf (dump_file, "ipa-prop: Discovered direct call to non-function"
+				" in (%s/%i).\n",
+		     cgraph_node_name (ie->caller), ie->caller->uid);
+	  return NULL;
+	}
+    }
   callee = cgraph_get_node (target);
-  if (!callee)
-    return NULL;
+
+  /* Because may-edges are not explicitely represented and vtable may be external,
+     we may create the first reference to the object in the unit.  */
+  if (!callee || callee->global.inlined_to)
+    {
+      struct cgraph_node *first_clone = callee;
+
+      /* We are better to ensure we can refer to it.
+	 In the case of static functions we are out of luck, since we already	
+	 removed its body.  In the case of public functions we may or may
+	 not introduce the reference.  */
+      if (!canonicalize_constructor_val (target, NULL)
+	  || !TREE_PUBLIC (target))
+	{
+	  if (dump_file)
+	    fprintf (dump_file, "ipa-prop: Discovered call to a known target "
+		     "(%s/%i -> %s/%i) but can not refer to it. Giving up.\n",
+		     xstrdup (cgraph_node_name (ie->caller)), ie->caller->uid,
+		     xstrdup (cgraph_node_name (ie->callee)), ie->callee->uid);
+	  return NULL;
+	}
+
+      /* Create symbol table node.  Even if inline clone exists, we can not take
+	 it as a target of non-inlined call.  */
+      callee = cgraph_create_node (target);
+
+      /* OK, we previously inlined the function, then removed the offline copy and
+	 now we want it back for external call.  This can happen when devirtualizing
+	 while inlining function called once that happens after extern inlined and
+	 virtuals are already removed.  In this case introduce the external node
+	 and make it available for call.  */
+      if (first_clone)
+	{
+	  first_clone->clone_of = callee;
+	  callee->clones = first_clone;
+	  symtab_prevail_in_asm_name_hash ((symtab_node)callee);
+	  symtab_insert_node_to_hashtable ((symtab_node)callee);
+	  if (dump_file)
+	    fprintf (dump_file, "ipa-prop: Introduced new external node "
+		     "(%s/%i) and turned into root of the clone tree.\n",
+		     xstrdup (cgraph_node_name (callee)), callee->uid);
+	}
+      else if (dump_file)
+	fprintf (dump_file, "ipa-prop: Introduced new external node "
+		 "(%s/%i).\n",
+		 xstrdup (cgraph_node_name (callee)), callee->uid);
+    }
   ipa_check_create_node_params ();
 
   /* We can not make edges to inline clones.  It is bug that someone removed
--- gcc/testsuite/g++.dg/ipa/devirt-11.C	(revision 0)
+++ gcc/testsuite/g++.dg/ipa/devirt-11.C	(revision 196177)
@@ -0,0 +1,50 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-ipa-inline" } */
+int baz ();
+struct A
+{
+  virtual int fn2 () = 0;
+  virtual int *fn3 ();
+  double *fn4 ();
+  int fn5 (int);
+  template <class T>
+  void fn1 (A &, T) { fn3 (); fn4 (); fn2 (); }
+};
+struct B : A
+{
+  int fn2 () { return 6; }
+  void fn3 (int, double);
+  B (bool = true);
+  B (int, int);
+};
+template <typename T>
+void
+foo (B &x, A &y, A &z)
+{
+  y.fn2 ();
+  z.fn2 ();
+  int i = baz ();
+  int j = (y.fn3 ())[i];
+  x.fn3 (j, (y.fn4 ())[i] + (z.fn4 ())[z.fn5 (j)]);
+}
+inline B
+operator+ (A &y, A &z)
+{
+  B x;
+  foo<int> (x, y, z);
+  return x;
+}
+void
+bar ()
+{
+  B a, b, c (4, 0), d;
+  a.fn1 (b, .6);
+  baz ();
+  c + d;
+}
+/* While inlining function called once we should devirtualize a new call to fn2
+   and two to fn3. While doing so the new symbol for fn2 needs to be
+   introduced.  */
+/* { dg-final { scan-ipa-dump-times "Discovered a virtual call to a known target" 3 "inline"  } } */
+/* { dg-final { scan-ipa-dump-times "and turned into root of the clone tree" 1 "inline"  } } */
+/* { dg-final { cleanup-ipa-dump "inline" } } */