Re: [Qemu-devel] [RFC v2 PATCH 01/13] Introduce TCGOpcode for memory barrier

[Richard Henderson]

On 06/06/2016 10:11 AM, Pranith Kumar wrote:
> If I read it correctly TCG_BAR_SYNC is equivalent to OR of all the
> other four barriers. I am not sure if we can just construct SYNC like
> this or if we need to define it explicitly though.

AFAICS, sparc membar #sync is stronger.

Compare PowerPC hwsync and lwsync.  I would define lwsync as the OR of the 
other 4 barriers, but hwsync as TCG_BAR_SYNC.


r~