MOVQ            Move Quadword to/from MMX Register

MOVQ destination, source                             CPU: MMX

        Logic   destination <- source

    MOVQ copies 64 bits from the source operand to the destination
    operand. The destination and source operands can be either MMX
    registers or 64-bit memory operands. MOVQ cannot transfer data from
    memory to memory.

    When the destination is an MMX register and the source is a 64-bit
    memory operand, the 64ábits of data at the memory location are
    copied into the MMX register. 

    When the destination is a 64-bit memory operand and the source is an
    MMX register, the 64ábits of data are copied from the MMX register
    into the memory location. 

    When the destination and source are both MMX registers, the contents
    of the MMX register (source) are copied into an MMX register
    (destination).


    Opcode      Format
    0F 6F /r    MOVQ mm, mm/m64
    0F 7F /r    MOVQ mm/m64, mm