A.5.324 UNPCKLPD: Unpack and Interleave Low Packed Double-Precision FP Data
UNPCKLPD xmm1,xmm2/m128 ; 66 0F 14 /r [WILLAMETTE,SSE2]
UNPCKLPD performs an interleaved unpack of the low-order data elements
of the source and destination operands, saving the result in "xmm1". It
ignores the lower half of the sources.
The operation of this instruction is:
dst[63-0] := dst[63-0];
dst[127-64] := src[63-0].