Which processor to test C++11/C11 acquire release semantic

I am looking for a processor that performs read acquire/store release with the same semantic as specified in the C11/C++11 standards.

x86 processor synchronization is much too strong so that it is impossible to test a lock-free algorithm using acquire/release semantic.

The same seems to apply to ARM processor because this architecture offers either stronger or weaker read/store synchronizations. Maybe ARMv8.3 may offer the right semantic but I believe there are no ARMv8.3 processor on the market.

On which processor or architecture should I test a lock-free algorithm using acquire-release semantic?