3 ms·Close. Sign extension. But this is a C puzzle, so I'd get away with "undefined behaviour".by mfukar 10y agoClose. Sign extension. But this is a C puzzle, so I'd get away with "undefined behaviour".mikeash 10y agoWhere does sign extension occur here?asamy45 10y agoThe movslq instruction will sign extend the upper 32 bits.mikeash 10y agoRight you are! Thanks. I tried to check, but didn't realize my test case had produced a zero bit in that position so didn't expose sign extension.