Re: Teach same_types_for_tbaa to structurally compare arrays, pointers and vectors

[Jan Hubicka]

Hi,
this is minimal version of patch adding just the pointer compare.
Bootstrapped/regtested x86_64-linux, makes sense? :)

Honza

        * tree-ssa-alias.c (same_type_for_tbaa): Return 1 if types
        same as pointers.

Index: tree-ssa-alias.c
===================================================================
--- tree-ssa-alias.c    (revision 271599)
+++ tree-ssa-alias.c    (working copy)
@@ -787,6 +787,10 @@ same_type_for_tbaa (tree type1, tree typ
   type1 = TYPE_MAIN_VARIANT (type1);
   type2 = TYPE_MAIN_VARIANT (type2);
 
+  /* Handle common case.  */
+  if (type1 == type2)
+    return 1;
+
   /* If we would have to do structural comparison bail out.  */
   if (TYPE_STRUCTURAL_EQUALITY_P (type1)
       || TYPE_STRUCTURAL_EQUALITY_P (type2))