BITCOST_ACCURACY
# define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
# define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
# define BITCOST_MULTIPLIER (1 << BITCOST_ACCURACY)
U32 const FWeight = (stat << BITCOST_ACCURACY) >> hb;
assert(hb + BITCOST_ACCURACY < 31);