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Date: Thu, 15 May 2003 22:17:24 +0200
From: Johan Rydberg <jrydberg@night.trouble.net>
Subject: Re: [Qemu-devel] [PATCH] Updated Sparc support
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To: "David S. Miller" <davem@redhat.com>
Cc: qemu-devel@nongnu.org

On 2003.05.15 22:05 David S. Miller wrote:

>    The reason for me asking is that I some time soon "port" my
> simulator
>    [1] to SPARC hosts, and it needs to have a lot of global registers
>    (more than those 6-7 available).
> 
> Just only execute the generated code in a fixed context and thus
> in the same register window, then at the call site into the generated
> code clobber all of the input registers.

The global registers will initially not be used for dynamic generated
code, but in the direct threaded interpreter.  Using global registers
for commonly used variables such as the CPU structure and current 
virtual
program counter will increase the performance with a magnitude I guess.

So, if I understand you correctly, everything should work pretty good
i you use -fflat and stay away from the input registers?  (I have no
need for the -fno-delay-slot flag)

> Just look at the qemu code, it works quite well.

Will do that aswell.

brgds,
Johan.