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Subject: Re: [Qemu-devel] Shifts, ppc[64], xtensa
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>, qemu-devel@nongnu.org, Aurelien Jarno <aurelien@aurel32.net>

On 09/19/2012 01:05 PM, Peter Maydell wrote:
> I notice tcg/README doesn't actually mention this restriction
> on goto_tb, incidentally.

Nor does it mention that only indicies 0 and 1 are valid.
I.e. no use of goto_tb $2 for multi-way branches.

> (I wonder if there are enough easily checkable and plausibly
> violated constraints on generated TCG to make it worth having
> a debug mode pass which checks them? "Only one goto_tb X per
> TB" is an easy check...)

Sure.  Enabled via the existing --enable-tcg-debug I would presume.


r~