[Bug tree-optimization/49760] vectorization inhibited if indices are references

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49760

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
           Keywords|                            |missed-optimization
   Last reconfirmed|                            |2011.07.18 08:57:31
                 CC|                            |rguenth at gcc dot gnu.org
     Ever Confirmed|0                           |1
           Severity|normal                      |enhancement

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-07-18 08:57:31 UTC ---
The issue is that *k may be aliased by a store to the int array pointed to
by out.  That is because the middle-end treats int & k the same as
int * k (not sure if there is a semantic difference in C++), so it might
as well point to out.a[27].  Which means int & k should be restrict
qualified as well (why even pass it as reference?)