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From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH v6 02/50] tcg: Propagate args to op->args
 in optimizer
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To: "Emilio G. Cota" <cota@braap.org>, Richard Henderson <richard.henderson@linaro.org>
Cc: qemu-devel@nongnu.org

On 10/17/2017 01:28 PM, Emilio G. Cota wrote:
>> -        TCGArg * const args = op->args;
> 
> Reviewed-by: Emilio G. Cota <cota@braap.org>
> 
> Just for my own education: why doesn't gcc generate the same code when
> leaving 'args' as above? I thought we could simplify the diff without
> any side effects, but it turns out that more code is generated.

Um... this patch was intended to be code cleanup only.  It should have
generated the same code.  I admit I didn't check.

That there is a code difference is surprising and probably reportable as a
compiler bug.


r~