Run MP+po+sync in model, using ppcmem
PPC MP+po+sync "PodWW Rfe SyncdRR Fre" Cycle=Rfe SyncdRR Fre PodWW { 0:r2=x; 0:r4=y; 1:r2=y; 1:r4=x; } P0 | P1 ; li r1,1 | lwz r1,0(r2) ; stw r1,0(r2) | sync ; li r3,1 | lwz r3,0(r4) ; stw r3,0(r4) | ; exists (1:r1=1 /\ 1:r3=0)