static uint64_t add(uint64_t dest[], uint64_t x[], uint64_t y[], uint32_t len) {
uint64_t carry = 0;
for (uint32_t i = 0; i< len; ++i) {
static uint64_t add(uint64_t dest[], uint64_t x[], uint64_t y[], uint32_t len) {
uint64_t carry = 0;
for (uint32_t i = 0; i< len; ++i) {
- uint64_t save = std::max(x[i],y[i]);
dest[i] = x[i] + y[i] + carry;
dest[i] = x[i] + y[i] + carry;
- carry = dest[i] < save ? 1 : 0;
+ uint64_t limit = std::min(x[i],y[i]);
+ carry = dest[i] < limit || (carry && dest[i] == limit);