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Date: Thu, 10 Jun 2010 15:08:07 -0700
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH 07/35] tcg: Optionally sign-extend 32-bit
	arguments for 64-bit host.
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To: Aurelien Jarno <aurelien@aurel32.net>
Cc: qemu-devel@nongnu.org, agraf@suse.de

On 06/10/2010 03:22 AM, Aurelien Jarno wrote:
> Wouldn't it be better to actually pass the whole flag to
> tcg_gen_helper32(), so that we can in the future also support mixed
> signedness in arguments? Also doing it here looks like a bit like a
> magic constant.

I suppose that's possible.

> This part allocates a lot of temp variables, that will probably generate
> a lot of register spills during the code generation.
> 
> As we do that for all arguments anyway, wouldn't it be possible to do
> the extension in place? The value in the register is changed, but that
> should not have any effect as it is ignored anyway in other
> instructions.

That hadn't occurred to me.  I'll give it a try.


r~