10% runtime regression in rnflow Polyhedron benchmark

[Uros Bizjak]

Hello!

Recent patch introduced 10% runtime regression on x86_64 targets in
rnflow Polyhedron benchmark [1]. Did somebody alread bisected to the
offending patch?

[1] http://gcc.opensuse.org/c++bench/polyhedron/polyhedron-summary.txt-2-0.html

Uros.