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Subject: Re: [Qemu-devel] [PATCH 17/21] target-arm: A64: add support for
 conditional compare insns
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Patch Tracking <patches@linaro.org>, Michael Matz <matz@suse.de>, QEMU Developers <qemu-devel@nongnu.org>, Claudio Fontana <claudio.fontana@linaro.org>, Dirk Mueller <dmueller@suse.de>, Will Newton <will.newton@linaro.org>, Laurent Desnogues <laurent.desnogues@gmail.com>, =?UTF-8?B?QWxleCBCZW5uw6ll?= <alex.bennee@linaro.org>, "kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>, Christoffer Dall <christoffer.dall@linaro.org>

On 12/19/2013 01:23 PM, Peter Maydell wrote:
> Hmm. I clearly don't entirely understand the rules here.
> The TCG README says "temporaries are only live
> in a basic block" and "After the end of a basic block, the
> content of temporaries is destroyed", which I took to
> mean that the value in the temp was dead after the
> branch, but that I could freely reuse it for something
> else afterwards as long as I wrote a new value to
> it (as we're doing here). I guess that's wrong?

You need to re-allocate it in each basic block.

We don't have enough tcg checking to find errors like this.


r~