lto-streamer-in.c (lto_read_body_or_constructor): Set TYPE_CANONICAL only for types where LTO sets them.

	* lto-streamer-in.c (lto_read_body_or_constructor): Set TYPE_CANONICAL
	only for types where LTO sets them.
	* tree.c (build_array_type_1): Do ont set TYPE_CANONICAL for LTO.
	(make_vector_type): Likewise.
	(gimple_canonical_types_compatible_p): Use canonical_type_used_p.
	* tree.h (canonical_type_used_p): New inline.
	* alias.c (get_alias_set): Handle structural equality for all
	types that pass canonical_type_used_p.
	(record_component_aliases): Look through all types with
	record_component_aliases for possible pointers; sanity check that
	the alias sets match.

	* lto.c (iterative_hash_canonical_type): Recruse for all types
	which pass !canonical_type_used_p.
	(gimple_register_canonical_type_1): Sanity check we do not compute
	canonical type of anything with !canonical_type_used_p.
	(gimple_register_canonical_type): Skip all types that are
	!canonical_type_used_p

From-SVN: r230835

1 files changed, 20 insertions, 1 deletions

diff --git a/gcc/tree.h b/gcc/tree.h
index 6c733aa..121c88b 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -4811,7 +4811,9 @@ extern void DEBUG_FUNCTION verify_type (const_tree t);
 extern bool gimple_canonical_types_compatible_p (const_tree, const_tree,
 						 bool trust_type_canonical = true);
 extern bool type_with_interoperable_signedness (const_tree);
-/* Return simplified tree code of type that is used for canonical type merging.  */
+
+/* Return simplified tree code of type that is used for canonical type
+   merging.  */
 inline enum tree_code
 tree_code_for_canonical_type_merging (enum tree_code code)
 {
@@ -4833,6 +4835,23 @@ tree_code_for_canonical_type_merging (enum tree_code code)
   return code;
 }
 
+/* Return ture if get_alias_set care about TYPE_CANONICAL of given type.
+   We don't define the types for pointers, arrays and vectors.  The reason is
+   that pointers are handled specially: ptr_type_node accesses conflict with
+   accesses to all other pointers.  This is done by alias.c.
+   Because alias sets of arrays and vectors are the same as types of their
+   elements, we can't compute canonical type either.  Otherwise we could go
+   form void *[10] to int *[10] (because they are equivalent for canonical type
+   machinery) and get wrong TBAA.  */
+
+inline bool
+canonical_type_used_p (const_tree t)
+{
+  return !(POINTER_TYPE_P (t)
+	   || TREE_CODE (t) == ARRAY_TYPE
+	   || TREE_CODE (t) == VECTOR_TYPE);
+}
+
 #define tree_map_eq tree_map_base_eq
 extern unsigned int tree_map_hash (const void *);
 #define tree_map_marked_p tree_map_base_marked_p