[Bug rtl-optimization/69052] [6 Regression] Performance regression after r229402.

[ienkovich at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69052

--- Comment #8 from Ilya Enkovich <ienkovich at gcc dot gnu.org> ---
(In reply to amker from comment #7)
> According to discussion at https://gcc.gnu.org/ml/gcc/2016-01/msg00190.html,
> hook is probably not wanted in this case.
> Bernd gave another proposal by moving combine before loop transforms is also
> interesting, but it can be for GCC6.
> So a backend fix would be nice.

Unfortunately my patch causes significant regressions in some SPEC benchmarks. 
Looks like address operands order matters in some other places.