9127 -> 8936 decicycles (fate-suite/vc1/SA10143.vc1)
13855 -> 10976 decicycles  (fate-suite/vc1/SA20021.vc1)
tests done by the author over this function but with the whole
patchset applied not just this commit
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>