[Bug fortran/53957] Polyhedron 11 benchmark: MP_PROP_DESIGN twice as long as other compiler

["rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53957

--- Comment #7 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-07-18 14:47:49 UTC ---
It helps to make us even consider the loop.  We now run into

696: worklist: examine stmt: D.2574_254 = (real(kind=4)) i_5;

696: vect_is_simple_use: operand i_5
696: def_stmt: i_5 = PHI <1(77), i_324(80)>

696: Unsupported pattern.
696: not vectorized: unsupported use in stmt.
696: unexpected pattern.

that is, the following induction is not handled:

                           phit = phib + phie(k) + (REAL(i)-0.50D0)     &
     &                            *dphit

so it would be still worthwhile to pursue your patch if it does not have
negative effects elsewhere.  We should be able to fix the induction code
to handle this case.

If you can help isolating the innermost two loops into a smaller testcase
that would be great, too.