Add statistics support for some optimizations

This patch adds support for the --dump-stats facility with some
optimizations
and fixes all build issues introduced by the patch:
I68751b119a030952a11057cb651a3c63e87e73ea (which got reverted)

Change-Id: I5af1f2a8cced0a1a55c2bb4d8c88e6f0a24ec879
Signed-off-by: Jean-Philippe Halimi <jean-philippe.halimi@intel.com>