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Date: Mon, 23 Oct 2006 11:04:24 -0700
From: "K. Richard Pixley" <rich.pixley@palmsource.com>
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Subject: Re: [Qemu-devel] qemu vs gcc4
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To: Paul Brook <paul@codesourcery.com>
Cc: qemu-devel@nongnu.org

Paul Brook wrote:
> Better to just teach qemu how to generate code.
> In fact I've already done most of the infrastructure (and a fair amount of the 
> legwork) for this. The only major missing function is code to do softmmu 
> load/store ops.
> https://nowt.dyndns.org/
Well, perhaps.  Except that with gcc, we get to leverage the ongoing gcc 
optimizations, bug fixes,  new cpu support, debugger support, etc.  
Granted, not all of these are going to be relevant to the qemu 
environment, but in a contest between gcc generated code and qemu 
generated code, I'll bet on gcc most days.

No doubt there are times when a gcc optimization takes so long that it 
costs more time to optimize than would be won back by the running code.  
Presumably, qemu generated code would be able to make better decisions 
here.  Except that we're not talking about using gcc in real time, are 
we?  So essentially we have near infinite time for optimizations.

--rich