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From: Richard Henderson <richard.henderson@linaro.org>
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Date: Wed, 13 Sep 2017 10:09:09 -0700
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Subject: Re: [Qemu-devel] [PATCH 4/7] tcg: Add support for "inlining"
 regions of code
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To: =?UTF-8?Q?Llu=c3=ads_Vilanova?= <vilanova@ac.upc.edu>, qemu-devel@nongnu.org
Cc: Stefan Hajnoczi <stefanha@redhat.com>, Richard Henderson <rth@twiddle.net>

On 09/10/2017 09:27 AM, Lluís Vilanova wrote:
> TCG BBLs and instructions have multiple exit points from where to raise
> tracing events, but some of the necessary information in the generic
> disassembly infrastructure is not available until after generating these
> exit points.
> 
> This patch adds support for "inline points" (where the tracing code will
> be placed), and "inline regions" (which identify the TCG code that must
> be inlined). The TCG compiler will basically copy each inline region to
> any inline points that reference it.

I am not keen on this.

Is there a reason you can't just emit the tracing code at the appropriate place
to begin with?  Perhaps I have to wait to see how this is used...


r~