dest[0] = dest[0] ^ source[0] dest[1] = dest[1] ^ source[1] dest[2] = dest[2] ^ source[2] dest[3] = dest[3] ^ source[3]
The xorps instruction xors the 4 source values (second operand) to the 4 values of the destination (an XMM register). The source can be an XMM register or a 32 bit memory location. There is also vxorps on CPUs with AVX instructions which allows using 3 XMM registers or 2 XMM registers and a memory location which can simplify coding and which xors 8 pairs of values if you use YMM registers.
There is also xorpd which xors packed doubles. The result is the same so pick your favorite.
xorps xmm0, xmm1 ; xor 4 pairs of values from xmm0 & xmm1 ; leave the rest of ymm0 as is xorps xmm0, [x] ; xor 4 pairs of values from xmm0 & x ; x is an array of floats ; leave the rest of ymm0 as is vxorps xmm3, xmm0, xmm15 ; xor 4 pairs of values from xmm0 & xmm15 ; store results in xmm3 vxorps ymm3, ymm0, [x] ; xor 8 pairs of values from ymm0 & x ; store results in ymm3 vxorps ymm3, ymm0, [rsi] ; xor 8 pairs of values from ymm0 & [rsi] ; rsi contains the address of an array ; store results in ymm3