C W+RWC+fencewmboncerelease+fencembonceonce+fencembonceacquire Hash=e490295314051a11b80e7769bf483dc0 Cycle=FreAcquireOnce FenceWmbdWWOnceRelease RfeReleaseOnce FenceMbdRROnceOnce FreOnceOnce FenceMbdWROnceAcquire Relax=FreAcquireOnce RfeReleaseOnce Safe=FenceMbdWR FenceMbdRR FenceWmbdWW 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=FenceWmbdWWOnceRelease RfeReleaseOnce FenceMbdRROnceOnce FreOnceOnce FenceMbdWROnceAcquire FreAcquireOnce {} P0(int* x,int* y) { WRITE_ONCE(*x,1); smp_wmb(); smp_store_release(y,1); } P1(int* y,int* z) { int r0 = READ_ONCE(*y); smp_mb(); int r1 = READ_ONCE(*z); } P2(int* x,int* z) { WRITE_ONCE(*z,1); smp_mb(); int r0 = smp_load_acquire(x); } Observed 2:r0=0; 1:r1=0; 1:r0=1;
C11 equivalent:
C W+RWC+fencewmboncerelease+fencembonceonce+fencembonceacquire Hash=e490295314051a11b80e7769bf483dc0 Cycle=FreAcquireOnce FenceWmbdWWOnceRelease RfeReleaseOnce FenceMbdRROnceOnce FreOnceOnce FenceMbdWROnceAcquire Relax=FreAcquireOnce RfeReleaseOnce Safe=FenceMbdWR FenceMbdRR FenceWmbdWW 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=FenceWmbdWWOnceRelease RfeReleaseOnce FenceMbdRROnceOnce FreOnceOnce FenceMbdWROnceAcquire FreAcquireOnce {} P0(atomic_int* x,atomic_int* y) { atomic_store_explicit(x,1,memory_order_relaxed); atomic_thread_fence(memory_order_acq_rel); 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_seq_cst); int r1 = atomic_load_explicit(z,memory_order_relaxed); } 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_acquire); } exists (1:r0=1 /\ 1:r1=0 /\ 2:r0=0)