Well, currently, it's 10 times slower (4 times using gcc -03)

nb: to use it
 lv6 lv6 dice5.lus -n dice5 -2c
 sh dice5.sh
 rdbgui4sasa -sut "./dice5.exec"

nb: requires
  - an up-to-data rdbg (available via git and opam)
  - an up-to-data sasa (git only)
enjoy :)