PCMPEQW         Packed Compare for Equal, Word

PCMPEQW destination, source                          CPU: MMX

        Logic   if mm(15..0)  = mm/m64(15..0)
                     mm(15..0)  <- 0FFFFh
                else mm(15..0)  <- 0
                endif
                if mm(31..16) = mm/m64(31..16)
                     mm(31..16) <- 0FFFFh
                else mm(31..16) <- 0
                endif
                if mm(47..32) = mm/m64(47..32)
                     mm(47..32) <- 0FFFFh
                else mm(47..32) <- 0
                endif
                if mm(63..48) = mm/m64(63..48)
                     mm(63..48) <- 0FFFFh
                else mm(63..48) <- 0
                endif

    PCMPEQ compares the words in the destination operand to the
    corresponding words in the source operand. If the data elements are
    equal, the corresponding data element in the destination register is
    set to all ones. If they are not equal, the corresponding data
    element is set to all zeros. 

    The destination operand is an MMX register. The source operand can
    either be an MMX register or a 64-bit memory operand.


    Opcode      Format
    0F 75 /r    PCMPEQW mm, mm/m64