MMX instruction for logical and not.

Unlike most MMX instructions, PAND doesn't operate on packed data. Instead, it operates on bits. A MMX register or 64 bit memory location is inverted, and combined with a MMX register (also inverted) using logical and. This would ordinarily require lots of MMX instructions:

pcmpeqb  mm7, mm7
pxor     mm7, mm0
pxor     mm7, mm1
pand     mm0, mm1

AT&T instruction ordering used: operator, source, destination.

Compare POR, PAND, PXOR