The EMMS instruction empties the MMX state. This instruction must be used to clear the MMX state (i.e. empty the floating-point tag word) at the end of an MMX routine before calling other routines that can execute floating-point instructions. If a floating-point instruction loads into one of the registers before it has been reset by the EMMS instruction, a floating-point stack overflow can occur, which results in an floating-point exception or incorrect result.
