[Bug rtl-optimization/60317] [4.9 Regression] find_hard_regno_for compile time hog in libvpx

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60317

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
This whole thing updating keys and such should use a proper lattice of
per-cgraph and per-edge node sizes/times which can be updated with a
less ad-hoc algorithm than the current one which easily and completely explodes
... :/  (and the 'cache' is completely ineffective during the update process)