> -----Original Message----- > From: lng-odp [mailto:lng-odp-boun...@lists.linaro.org] On Behalf Of Maxim > Uvarov > Sent: Wednesday, June 6, 2018 4:26 PM > To: Maxim Kuvyrkov <maxim.kuvyr...@linaro.org> > Cc: LNG ODP Mailman List <lng-odp@lists.linaro.org> > Subject: [lng-odp] armv8 gcc lock free instructions > > Hello Maxim, > > we have discussion here that gcc for armv8 does not generated lock free > instructions for 64 bit types. But all other arched do. > > https://github.com/Linaro/odp/pull/611 > > Do you know reasons for that? > > Thank you, > Maxim.
The question is: why 128 bit GCC built-in atomics are not lock-free on ARMv8 (__atomic_is_lock_free(16) returns false)? ARMv8.0 ISA has dual 64bit atomic instructions available. -Petri
