VeriusTIL memcpy can be implemented with a single instruction "rep movsb" (after setting ESI (src ptr), EDI (dst ptr) and ECX (len) registers).
Pietro Gagliardi@verius @KitRedgrave you can also use movsw, movsd, movsq, etc. if you want to move larger sized chunks, and there's also stos* and a few others but I forget what they do different