PPC mcs (PPCMTwelveSync) { x=0 ; y=0; 0:r4=x ; 0:r5=y; 1:r4=x ; 1:r5=y; 2:r4=x ; 2:r2=2 ; 3:r5=y ; 3:r1=1 ; 0:r1=1 ; 0:r2=2 ; 1:r3=3; } P0 | P1 | P2 | P3 ; stw r2,0(r5) | stw r3,0(r4) | stw r2,0(r4) |stw r1,0(r5) ; sync | sync | | ; stw r1,0(r4) | lwz r2,0(r5) | | ; locations [1:r2; x; y;] ~exists ( (1:r2=0 /\ x=3 /\ y=1) \/ (1:r2=0 /\ x=3 /\ y=2) \/ (1:r2=1 /\ x=3 /\ y=2) )