RFR (S): CR 8004318/JEP 171 Fences intrinsics

[Doug Lea]

On 12/03/12 17:40, Vitaly Davidovich wrote:
> Hi Aleksey,
>
> Why not have a bit more fine grained methods? OrderAccess in the VM has
> operations matching JMM wording: loadload, storestore, loadstore, storeload.

By convention these days, in sparc-ese,
"loadFence"  => LOAD_LOAD|LOAD_STORE
"storeFence" => STORE_STORE|LOAD_STORE
"fullFence"  => STORE_LOAD|LOAD_LOAD|STORE_STORE|LOAD_STORE

Which maps exactly to internals in hotspot, and other VMs,
and most processors(*) and to the non-exotic C11/C++11 modes.
So there's  nothing  else you'd be tempted to support.

(*) except, famously, POWER and pre-ARMV8/ARM64 ARM, which
are always a bit of an adventure to map. Luckily, upcoming
ARMV8 is a breeze though.

-Doug