NASM 2.05 based x86 Instruction Reference[ch362]

A.5.336 XORPD: Bitwise Logical XOR of Double-Precision FP Values XORPD xmm1,xmm2/m128 ; 66 0F 57 /r [WILLAMETTE,SSE2] XORPD returns a bit-wise logical XOR between the source and destination operands, storing the result in the destination operand.