TICKS_PER_HOUR
tmp -= TICKS_PER_HOUR / 2LL;
tmp += TICKS_PER_HOUR / 2LL;
tmp = div_s64(tmp, TICKS_PER_HOUR);
tmp = offset * (s64)TICKS_PER_HOUR;
tmp -= TICKS_PER_HOUR / 2LL;
tmp += TICKS_PER_HOUR / 2LL;
tmp = div_s64(tmp, TICKS_PER_HOUR);
tmp = offset * TICKS_PER_HOUR;