Moves a double quadword containing two packed double-precision floating-point values from the source operand (second operand) to the destination operand (first operand). This instruction can be used to load an XMM register from a 128-bit memory location, store the contents of an XMM register into a 128-bit memory location, or move data between two XMM registers. When the source or destination operand is a memory operand, the operand may be unaligned on a 16- byte boundary without causing a general-protection exception (#GP) to be generated.

To move double-precision floating-point values to and from memory locations that are known to be aligned on 16-byte boundaries, use the MOVAPD instruction.

While executing in 16-bit addressing mode, a linear address for a 128-bit data access that overlaps the end of a 16-bit segment is not allowed and is defined as reserved behavior. A specific processor implementation may or may not generate a general-protection exception (#GP) in this situation, and the address that spans the end of the segment may or may not wrap around to the beginning of the segment.

Destination = Source;