log2_mul_t
#define log2_mul(a, b_lg2) log2_mul_t(pt_vaddr_t, a, b_lg2)
#define oalog2_mul(a, b_lg2) log2_mul_t(pt_oaddr_t, a, b_lg2)
static_assert(log2_mul_t(unsigned int, 2, 2) == 8);