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From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [RFC v2 PATCH 02/13] tcg/i386: Add support for
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To: Pranith Kumar <bobby.prani@gmail.com>, "open list:i386 target" <qemu-devel@nongnu.org>
Cc: alex.bennee@linaro.org, serge.fdrv@linaro.org

On 05/31/2016 11:39 AM, Pranith Kumar wrote:
> +    case INDEX_op_mb:
> +        tcg_out_mb(s);

You need to look at the barrier type and DTRT.  In particular, the Linux 
smp_rmb and smp_wmb types need not emit any code.

> +    { INDEX_op_mb, { "r" } },

You certainly do *not* need the constant argument loaded into a register.  This 
should remain { }.


r~