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Subject: Re: [Qemu-devel] target-i386: guest variable shift by 0 provokes
	shift by -1
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>

On 03/18/2014 07:47 AM, Peter Maydell wrote:
> The interesting question is not immediate shifts
> but variable ones. It's trivially easy for the frontend
> to avoid passing out of range immediate values
> and for the backend to screen them out. This
> case is a variable shift TCG op.

Exactly how are you distinguishing between constant and variable shifts?  By
how they were issued in the first place?  By how they are presented to the backend?

Otherwise I'm not following you.


r~