C WWC+fencembonceonce+pooncerelease+Once Hash=9bbaab2417959af2a1732eda1febafa7 Cycle=RfeOnceOnce FenceMbdRWOnceOnce RfeOnceOnce PodRWOnceRelease WseReleaseOnce Relax=WseReleaseOnce Safe=FenceMbdRW RfeOnceOnce PodRWOnceRelease Generator=diy7 (version 7.46+3) Prefetch=1:x=F,1:y=W,2:y=F,2:x=W Com=Rf Rf Ws Orig=RfeOnceOnce FenceMbdRWOnceOnce RfeOnceOnce PodRWOnceRelease WseReleaseOnce {} P0(int* x) { WRITE_ONCE(*x,2); } P1(int* x,int* y) { int r0 = READ_ONCE(*x); smp_mb(); WRITE_ONCE(*y,1); } P2(int* x,int* y) { int r0 = READ_ONCE(*y); smp_store_release(x,1); } Observed x=2; 2:r0=1; 1:r0=2;
C11 equivalent:
C WWC+fencembonceonce+pooncerelease+Once Hash=9bbaab2417959af2a1732eda1febafa7 Cycle=RfeOnceOnce FenceMbdRWOnceOnce RfeOnceOnce PodRWOnceRelease WseReleaseOnce Relax=WseReleaseOnce Safe=FenceMbdRW RfeOnceOnce PodRWOnceRelease Generator=diy7 (version 7.46+3) Prefetch=1:x=F,1:y=W,2:y=F,2:x=W Com=Rf Rf Ws Orig=RfeOnceOnce FenceMbdRWOnceOnce RfeOnceOnce PodRWOnceRelease WseReleaseOnce {} P0(atomic_int* x) { atomic_store_explicit(x,2,memory_order_relaxed); } P1(atomic_int* x,atomic_int* y) { int r0 = atomic_load_explicit(x,memory_order_relaxed); atomic_thread_fence(memory_order_seq_cst); atomic_store_explicit(y,1,memory_order_relaxed); } P2(atomic_int* x,atomic_int* y) { int r0 = atomic_load_explicit(y,memory_order_relaxed); atomic_store_explicit(x,1,memory_order_release); } exists (x=2 /\ 1:r0=2 /\ 2:r0=1)