sparsebit_all_set
bool sparsebit_all_set(const struct sparsebit *sbit);
return !sparsebit_all_set(s);
assert(sparsebit_all_set(s));
assert(!sparsebit_all_set(s));
assert(sparsebit_all_set(s));
assert(!sparsebit_all_set(s));
assert(s->num_set >= num_set || sparsebit_all_set(s));
assert(s->num_set > 0 || sparsebit_all_set(s));