NASM 2.05 based x86 Instruction Reference[ch082]
A.5.62 DIVSD: Scalar Double-Precision FP Divide DIVSD xmm1,xmm2/mem64 ; F2 0F 5E /r [WILLAMETTE,SSE2] DIVSD divides the low-order double-precision FP value in the destination operand by the low-order double-precision FP value in the source operand, and stores the double-precision result in the destination register. The destination is an XMM register. The source operand can be either an XMM register or a 64-bit memory location. dst[0-63] := dst[0-63] / src[0-63], dst[64-127] remains unchanged.