NASM 2.05 based x86 Instruction Reference[ch182]

A.5.160 MOVDQ2Q: Move Quadword from XMM to MMX register. MOVDQ2Q mm,xmm ; F2 OF D6 /r [WILLAMETTE,SSE2] MOVDQ2Q moves the low quadword from the source operand to the destination operand.