lto.c (hash_canonical_type): Be sure we hash only types that need alias set.

	* lto.c (hash_canonical_type): Be sure we hash only types that
	need alias set.
	(gimple_register_canonical_type_1): Do not produce canonical
	types for types that do not need alias sets.
	* tree.c (gimple_canonical_types_compatible_p): Sanity check that
	we do not try to compute canonical type for type that does not need
	alias set.
	(verify_type): Drop FIXME for METHOD_TYPE, update FIXME for
	FUNCITON_TYPE.
	* tree.h (type_with_alias_set_p): New.

From-SVN: r223608

1 files changed, 20 insertions, 0 deletions

diff --git a/gcc/tree.h b/gcc/tree.h
index 2bac698..0b7b523 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -5090,6 +5090,26 @@ int_bit_position (const_tree field)
 	  + wi::to_offset (DECL_FIELD_BIT_OFFSET (field))).to_shwi ();
 }
 
+/* Return true if it makes sense to consider alias set for a type T.  */
+
+inline bool
+type_with_alias_set_p (const_tree t)
+{
+  /* Function and method types are never accessed as memory locations.  */
+  if (TREE_CODE (t) == FUNCTION_TYPE || TREE_CODE (t) == METHOD_TYPE)
+    return false;
+
+  if (COMPLETE_TYPE_P (t))
+    return true;
+
+  /* Incomplete types can not be accessed in general except for arrays
+     where we can fetch its element despite we have no array bounds.  */
+  if (TREE_CODE (t) == ARRAY_TYPE && COMPLETE_TYPE_P (TREE_TYPE (t)))
+    return true;
+
+  return false;
+}
+
 extern void gt_ggc_mx (tree &);
 extern void gt_pch_nx (tree &);
 extern void gt_pch_nx (tree &, gt_pointer_operator, void *);