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Subject: Re: [Qemu-devel] [RFC v2 PATCH 01/13] Introduce TCGOpcode for
 memory barrier
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To: Pranith Kumar <bobby.prani@gmail.com>, Sergey Fedorov <serge.fdrv@gmail.com>
Cc: "open list:All patches CC here" <qemu-devel@nongnu.org>, =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>

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~