Remove comparison for polymorphic types.

2019-10-30  Martin Liska  <mliska@suse.cz>

	* ipa-icf-gimple.c (func_checker::func_checker): Do not
	initialize m_compare_polymorphic.
	(func_checker::compare_decl): Do not compare polymorphic types.
	* ipa-icf-gimple.h (m_compare_polymorphic): Remove.
	* ipa-icf.c (sem_function::equals_private): Do not call
	compare_polymorphic_p.

From-SVN: r277617

gcc/ChangeLog

 2019-10-30  Martin Liska  <mliska@suse.cz>
 
+	* ipa-icf-gimple.c (func_checker::func_checker): Do not
+	initialize m_compare_polymorphic.
+	(func_checker::compare_decl): Do not compare polymorphic types.
+	* ipa-icf-gimple.h (m_compare_polymorphic): Remove.
+	* ipa-icf.c (sem_function::equals_private): Do not call
+	compare_polymorphic_p.
+
+2019-10-30  Martin Liska  <mliska@suse.cz>
+
 	* ipa-icf-gimple.c (func_checker::compare_ssa_name): Call
 	compare_operand.
 	(func_checker::compare_memory_operand): Remove.

gcc/ipa-icf-gimple.c

@@ -51,14 +51,12 @@ namespace ipa_icf_gimple {
    of declarations that can be skipped.  */
 
 func_checker::func_checker (tree source_func_decl, tree target_func_decl,
-			    bool compare_polymorphic,
 			    bool ignore_labels,
 			    hash_set<symtab_node *> *ignored_source_nodes,
 			    hash_set<symtab_node *> *ignored_target_nodes)
   : m_source_func_decl (source_func_decl), m_target_func_decl (target_func_decl),
     m_ignored_source_nodes (ignored_source_nodes),
     m_ignored_target_nodes (ignored_target_nodes),
-    m_compare_polymorphic (compare_polymorphic),
     m_ignore_labels (ignore_labels)
 {
   function *source_func = DECL_STRUCT_FUNCTION (source_func_decl);
@@ -156,23 +154,7 @@ func_checker::compare_decl (tree t1, tree t2)
   if (!compatible_types_p (TREE_TYPE (t1), TREE_TYPE (t2)))
     return return_false ();
 
-  /* TODO: we are actually too strict here.  We only need to compare if
-     T1 can be used in polymorphic call.  */
-  if (TREE_ADDRESSABLE (t1)
-      && m_compare_polymorphic
-      && !compatible_polymorphic_types_p (TREE_TYPE (t1), TREE_TYPE (t2),
-					  false))
-    return return_false ();
-
-  if ((t == VAR_DECL || t == PARM_DECL || t == RESULT_DECL)
-      && DECL_BY_REFERENCE (t1)
-      && m_compare_polymorphic
-      && !compatible_polymorphic_types_p (TREE_TYPE (t1), TREE_TYPE (t2),
-					  true))
-    return return_false ();
-
   bool existed_p;
-
   tree &slot = m_decl_map.get_or_insert (t1, &existed_p);
   if (existed_p)
     return return_with_debug (slot == t2);

gcc/ipa-icf-gimple.h

@@ -128,7 +128,6 @@ public:
      Similarly, IGNORE_SOURCE_DECLS and IGNORE_TARGET_DECLS are sets
      of declarations that can be skipped.  */
   func_checker (tree source_func_decl, tree target_func_decl,
-		bool compare_polymorphic,
 		bool ignore_labels = false,
 		hash_set<symtab_node *> *ignored_source_nodes = NULL,
 		hash_set<symtab_node *> *ignored_target_nodes = NULL);
@@ -258,9 +257,6 @@ private:
   /* Label to basic block index mapping.  */
   hash_map <tree, int> m_label_bb_map;
 
-  /* Flag if polymorphic comparison should be executed.  */
-  bool m_compare_polymorphic;
-
   /* Flag if ignore labels in comparison.  */
   bool m_ignore_labels;
 

gcc/ipa-icf.c

@@ -845,7 +845,6 @@ sem_function::equals_private (sem_item *item)
     return return_false ();
 
   m_checker = new func_checker (decl, m_compared_func->decl,
-				compare_polymorphic_p (),
 				false,
 				&refs_set,
 				&m_compared_func->refs_set);