XADD
Usage: XADD dest,src Modifies flags: AF CF OF PF SF ZF
Exchange and Add
XADD r/m8,reg8 ; 0F C0 /r [486]
XADD r/m16,reg16 ; o16 0F C1 /r [486]
XADD r/m32,reg32 ; o32 0F C1 /r [486]
XADD exchanges the values in its two operands, and then adds them together and writes the result into the destination (first) operand. This instruction can be used with a LOCK prefix for multi-processor synchronisation purposes.
EXAMPLE:
mov eax 00_0000_1111
mov ecx 10
xadd eax ecx ; eax = 25d > 19h