tree.c (reference_alias_ptr_type): New function.

2010-07-05  Richard Guenther  <rguenther@suse.de>

	* tree.c (reference_alias_ptr_type): New function.
	* tree.h (reference_alias_ptr_type): Declare.
	* tree-ssa-loop-ivopts.c (copy_ref_info): Restructure to
	allow non-TARGET_MEM_REF new refs.
	(rewrite_use_address): Pass old alias pointer type to
	create_mem_ref.
	* tree-ssa-address.c (create_mem_ref_raw): Get alias pointer type.
	Build a MEM_REF instead of a TARGET_MEM_REF if possible.
	(create_mem_ref): Get alias pointer type.  Adjust calls to
	create_mem_ref_raw.
	(maybe_fold_tmr): Likewise.
	* tree-flow.h (create_mem_ref): Adjust prototype.

From-SVN: r161840

1 files changed, 19 insertions, 0 deletions

diff --git a/gcc/tree.c b/gcc/tree.c
index cb2c276..e6deacc 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -3913,6 +3913,25 @@ mem_ref_offset (const_tree t)
 			  TYPE_PRECISION (TREE_TYPE (toff)));
 }
 
+/* Return the pointer-type relevant for TBAA purposes from the
+   gimple memory reference tree T.  This is the type to be used for
+   the offset operand of MEM_REF or TARGET_MEM_REF replacements of T.  */
+
+tree
+reference_alias_ptr_type (const_tree t)
+{
+  const_tree base = t;
+  while (handled_component_p (base))
+    base = TREE_OPERAND (base, 0);
+  if (TREE_CODE (base) == MEM_REF)
+    return TREE_TYPE (TREE_OPERAND (base, 1));
+  else if (TREE_CODE (base) == TARGET_MEM_REF
+	   || TREE_CODE (base) == MISALIGNED_INDIRECT_REF)
+    return NULL_TREE;
+  else
+    return build_pointer_type (TYPE_MAIN_VARIANT (TREE_TYPE (base)));
+}
+
 /* Similar except don't specify the TREE_TYPE
    and leave the TREE_SIDE_EFFECTS as 0.
    It is permissible for arguments to be null,