PCB_KERNNPX
pcb->pcb_flags |= PCB_KERNNPX | PCB_NPXNOSAVE | PCB_NPXINITDONE;
pcb->pcb_flags |= PCB_KERNNPX;
pcb->pcb_flags &= ~PCB_KERNNPX;
pcb->pcb_flags &= ~(PCB_NPXINITDONE | PCB_KERNNPX);
curpcb->pcb_flags |= PCB_KERNNPX | PCB_KERNNPX_THR;
PCB_KERNNPX | PCB_KERNNPX_THR);
MPASS((pcb2->pcb_flags & (PCB_KERNNPX | PCB_KERNNPX_THR)) == 0);
#define PCB_USER_FPU(pcb) (((pcb)->pcb_flags & PCB_KERNNPX) == 0)