C PeterZ Hash=ac728c456ed1636aa873c0a400fbecaf Generator=diyone7 (version 7.46+3) Prefetch=0:x=F,0:y=T,1:y=F,1:z=W,2:z=F,2:x=T Com=Fr Rf Fr Orig=FenceMbdWROnceOnce FreOnceOnce PodWWOnceRelease RfeReleaseAcquire FenceMbdRRAcquireOnce FreOnceOnce {} P0(int* x,int* y) { WRITE_ONCE(*x,1); smp_mb(); int r0 = READ_ONCE(*y); } P1(int* y,int* z) { WRITE_ONCE(*y,1); smp_store_release(z,1); } P2(int* x,int* z) { int r0 = smp_load_acquire(z); smp_mb(); int r1 = READ_ONCE(*x); } Observed 2:r1=0; 2:r0=1; 0:r0=0;
C11 equivalent:
C PeterZ Hash=ac728c456ed1636aa873c0a400fbecaf Generator=diyone7 (version 7.46+3) Prefetch=0:x=F,0:y=T,1:y=F,1:z=W,2:z=F,2:x=T Com=Fr Rf Fr Orig=FenceMbdWROnceOnce FreOnceOnce PodWWOnceRelease RfeReleaseAcquire FenceMbdRRAcquireOnce FreOnceOnce {} P0(atomic_int* x,atomic_int* y) { atomic_store_explicit(x,1,memory_order_relaxed); atomic_thread_fence(memory_order_seq_cst); int r0 = atomic_load_explicit(y,memory_order_relaxed); } P1(atomic_int* y,atomic_int* z) { atomic_store_explicit(y,1,memory_order_relaxed); atomic_store_explicit(z,1,memory_order_release); } P2(atomic_int* x,atomic_int* z) { int r0 = atomic_load_explicit(z,memory_order_acquire); atomic_thread_fence(memory_order_seq_cst); int r1 = atomic_load_explicit(x,memory_order_relaxed); } exists (0:r0=0 /\ 2:r0=1 /\ 2:r1=0)