A.5.250 PSADBW: Packed Sum of Absolute Differences
PSADBW mm1,mm2/m64 ; 0F F6 /r [KATMAI,MMX]
PSADBW xmm1,xmm2/m128 ; 66 0F F6 /r [WILLAMETTE,SSE2]
PSADBW The PSADBW instruction computes the absolute value of the
difference of the packed unsigned bytes in the two source operands.
These differences are then summed to produce a word result in the lower
16-bit field of the destination register; the rest of the register is
cleared. The destination operand is an MMX or an XMM register. The
source operand can either be a register or a memory operand.