C W+RWC+fencemboncerelease+fencermbonceacquire+fencembonceonce Hash=b051e2b55dbafac9622f4ffa667936e8 Cycle=FreAcquireOnce FenceMbdWROnceOnce FreOnceOnce FenceMbdWWOnceRelease RfeReleaseOnce FenceRmbdRROnceAcquire Relax=FreAcquireOnce RfeReleaseOnce Safe=FenceMbdWW FenceMbdWR FenceRmbdRR FreOnceOnce Generator=diy7 (version 7.46+3) Prefetch=0:x=F,0:y=W,1:y=F,1:z=T,2:z=F,2:x=T Com=Rf Fr Fr Orig=FenceMbdWWOnceRelease RfeReleaseOnce FenceRmbdRROnceAcquire FreAcquireOnce FenceMbdWROnceOnce FreOnceOnce {} P0(int* x,int* y) { WRITE_ONCE(*x,1); smp_mb(); smp_store_release(y,1); } P1(int* y,int* z) { int r0 = READ_ONCE(*y); smp_rmb(); int r1 = smp_load_acquire(z); } P2(int* x,int* z) { WRITE_ONCE(*z,1); smp_mb(); int r0 = READ_ONCE(*x); } Observed 2:r0=0; 1:r1=0; 1:r0=1;
C11 equivalent:
C W+RWC+fencemboncerelease+fencermbonceacquire+fencembonceonce Hash=b051e2b55dbafac9622f4ffa667936e8 Cycle=FreAcquireOnce FenceMbdWROnceOnce FreOnceOnce FenceMbdWWOnceRelease RfeReleaseOnce FenceRmbdRROnceAcquire Relax=FreAcquireOnce RfeReleaseOnce Safe=FenceMbdWW FenceMbdWR FenceRmbdRR FreOnceOnce Generator=diy7 (version 7.46+3) Prefetch=0:x=F,0:y=W,1:y=F,1:z=T,2:z=F,2:x=T Com=Rf Fr Fr Orig=FenceMbdWWOnceRelease RfeReleaseOnce FenceRmbdRROnceAcquire FreAcquireOnce FenceMbdWROnceOnce FreOnceOnce {} P0(atomic_int* x,atomic_int* y) { atomic_store_explicit(x,1,memory_order_relaxed); atomic_thread_fence(memory_order_seq_cst); atomic_store_explicit(y,1,memory_order_release); } P1(atomic_int* y,atomic_int* z) { int r0 = atomic_load_explicit(y,memory_order_relaxed); atomic_thread_fence(memory_order_acq_rel); int r1 = atomic_load_explicit(z,memory_order_acquire); } P2(atomic_int* x,atomic_int* z) { atomic_store_explicit(z,1,memory_order_relaxed); atomic_thread_fence(memory_order_seq_cst); int r0 = atomic_load_explicit(x,memory_order_relaxed); } exists (1:r0=1 /\ 1:r1=0 /\ 2:r0=0)