3 ms·
Yes, quite a bit stronger.
by hansvm 6y ago
Yes, quite a bit stronger.
- chrisseaton 6y agoIn guarantees the order of visibility of writes to shared locations. It dose not guarantee the granularity of updates to the shared locations, which is the essential difference here. How do you observe the difference between the three instructions just naturally happening to all run before your next instruction completes, and them eliding the memory operation as is happening in this optimisation? It's like the ABA problem - how do you differentiate between just never happening to see a B out of chance, and B being elided instead? You can't.