PR ipa/59831

	* g++.dg/ipa/devirt-24.C: New testcase.

	* ipa-cp.c (ipa_get_indirect_edge_target_1): Give up on -fno-devirtualize;
	Try to devirtualize by the knowledge of virtual table pointer given by
	aggregate propagation.
	* ipa-prop.c (try_make_edge_direct_virtual_call): Likewise.
	ipa_print_node_jump_functions): Dump also offset that
	is relevant for polymorphic calls.
	(determine_known_aggregate_parts): Add arg_type parameter; use it
	instead of determining the type from pointer type.
	(ipa_compute_jump_functions_for_edge): Update call of
	determine_known_aggregate_parts.
	* gimple-fold.c (gimple_get_virt_method_for_vtable): Break out from ...
	(gimple_get_virt_method_for_binfo): ... here; simplify using
	vtable_pointer_value_to_vtable.
	* gimple-fold.h (gimple_get_virt_method_for_vtable): Declare.
	* ipa-devirt.c (subbinfo_with_vtable_at_offset): Turn OFFSET parameter
	to unsigned HOST_WIDE_INT; Use vtable_pointer_value_to_vtable.
	(vtable_pointer_value_to_vtable): Break out from ...; handle also
	POINTER_PLUS_EXPR.
	(vtable_pointer_value_to_binfo): ... here.
	* ipa-utils.h (vtable_pointer_value_to_vtable): Declare.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@207439 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 41 insertions, 2 deletions

diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index 10fa4b6c236..18a5a03a5e1 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -1479,7 +1479,7 @@ ipa_get_indirect_edge_target_1 (struct cgraph_edge *ie,
   HOST_WIDE_INT token, anc_offset;
   tree otr_type;
   tree t;
-  tree target;
+  tree target = NULL;
 
   if (param_index == -1
       || known_vals.length () <= (unsigned int) param_index)
@@ -1527,14 +1527,53 @@ ipa_get_indirect_edge_target_1 (struct cgraph_edge *ie,
 	return NULL_TREE;
     }
 
+  if (!flag_devirtualize)
+    return NULL_TREE;
+
   gcc_assert (!ie->indirect_info->agg_contents);
   token = ie->indirect_info->otr_token;
   anc_offset = ie->indirect_info->offset;
   otr_type = ie->indirect_info->otr_type;
 
-  t = known_vals[param_index];
+  t = NULL;
+
+  /* Try to work out value of virtual table pointer value in replacemnets.  */
+  if (!t && agg_reps && !ie->indirect_info->by_ref)
+    {
+      while (agg_reps)
+	{
+	  if (agg_reps->index == param_index
+	      && agg_reps->offset == ie->indirect_info->offset
+	      && agg_reps->by_ref)
+	    {
+	      t = agg_reps->value;
+	      break;
+	    }
+	  agg_reps = agg_reps->next;
+	}
+    }
+
+  /* Try to work out value of virtual table pointer value in known
+     aggregate values.  */
+  if (!t && known_aggs.length () > (unsigned int) param_index
+      && !ie->indirect_info->by_ref)
+    {
+       struct ipa_agg_jump_function *agg;
+       agg = known_aggs[param_index];
+       t = ipa_find_agg_cst_for_param (agg, ie->indirect_info->offset,
+				       true);
+    }
+
+  /* If we found the virtual table pointer, lookup the binfo.  */
+  if (t)
+    t = vtable_pointer_value_to_binfo (t);
+
+  /* Did we work out BINFO via type propagation?  */
   if (!t && known_binfos.length () > (unsigned int) param_index)
     t = known_binfos[param_index];
+  /* Or do we know the constant value of pointer?  */
+  if (!t)
+    t = known_vals[param_index];
   if (!t)
     return NULL_TREE;