tree-optimization/119044 - predcom fails to preserve alias info

Predictive commoning fails to preserve alias info for the refs it
creates.  The following adds this to see whether it fixes the
observed regression in 436.cactusADM after r15-7665.

	PR tree-optimization/119044
	* tree-predcom.cc (ref_at_iteration): Copy alias info
	from the original ref.

diff --git a/gcc/tree-predcom.cc b/gcc/tree-predcom.cc
index d45aa3857b9fa752fa8809778b8da336a8c82dec..509d112a0a06fdfd440e128eeee3b6d36b894f1c 100644 (file)
--- a/gcc/tree-predcom.cc
+++ b/gcc/tree-predcom.cc
@@ -234,6 +234,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-affine.h"
 #include "builtins.h"
 #include "opts.h"
+#include "tree-ssa-address.h"
 
 /* The maximum number of iterations between the considered memory
    references.  */
@@ -1824,6 +1825,7 @@ ref_at_iteration (data_reference_p dr, int iter,
   tree type = build_aligned_type (TREE_TYPE (ref),
                                  get_object_alignment (ref));
   ref = build2 (MEM_REF, type, addr, alias_ptr);
+  copy_ref_info (ref, DR_REF (dr));
   if (ref_type)
     ref = build3 (ref_code, ref_type, ref, ref_op1, ref_op2);
   return ref;