PPC RWC+lwsync+sync "Rfe LwSyncdRR Fre SyncdWR Fre" Cycle=Rfe LwSyncdRR Fre SyncdWR Fre { 0:r2=x; 1:r2=x; 1:r4=y; 2:r2=y; 2:r4=x; } P0 | P1 | P2 ; li r1,1 | lwz r1,0(r2) | li r1,1 ; stw r1,0(r2) | lwsync | stw r1,0(r2) ; | lwz r3,0(r4) | sync ; | | lwz r3,0(r4) ; exists (1:r1=1 /\ 1:r3=0 /\ 2:r3=0)