3 ms·
The REX prefix is redundant for 'movsb', but not 'movsd'/'movsq' (moving either 32- or 64-bit words, depending on the prefix). That may have something to do wit
by rep_lodsb 3y ago
The REX prefix is redundant for 'movsb', but not 'movsd'/'movsq' (moving either 32- or 64-bit words, depending on the prefix). That may have something to do with the bug, if there is any shared microcode between those instructions?