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Date: Mon, 21 Dec 2009 11:03:23 +0100
Message-ID: <761ea48b0912210203u6eb6e46ax4ec63ad8a383c490@mail.gmail.com>
From: Laurent Desnogues <laurent.desnogues@gmail.com>
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Subject: [Qemu-devel] Re: [PATCH 0/5] tcg conditional set, round 4
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org, Paul Brook <paul@codesourcery.com>, aurelien@aurel32.net, Richard Henderson <rth@twiddle.net>

On Mon, Dec 21, 2009 at 10:47 AM, Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 12/21/2009 10:13 AM, Laurent Desnogues wrote:
>>
>> Which front-ends would need it and would the cost to generate
>> code for it on some (most?) back-ends be amortized?
>
> The ARM front-end could definitely use a backend's ability to do predication
> (via movcond).

I think most things done in the ARM front-end can be done
with a simpler movcond that'd be:

   movcond cond, arg_cond1, arg_cond2, dest, vtrue

though as Richard said this could impact tcg reg alloc and
liveness analysis.

Also, I wonder what would be the impact on speed.


Laurent