LMHI20
ull_ax0 = ull_x0 + (LMROUND & LMHI20);
ull_ax##I = ((ull_x##I + LMROUND) & LMHI20); \
ull_ax##I = (ull_x##I + (LMROUND & LMHI20)); \
unsigned long long LMHI20 = ((unsigned long long*)LCONST)[6]; /* 0xfffff00000000000 */