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Date: Thu, 17 Jun 2010 11:14:33 -0700
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] VLIW?
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To: "Gibbons, Scott" <sgibbons@qualcomm.com>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

On 06/17/2010 11:05 AM, Gibbons, Scott wrote:
> My architecture is an Interleaved Multithreading VLIW architecture.
> One bundle (packet) executes per processor cycle, rotating between
> threads (i.e., thread 0 executes at time 0, thread 1 executes at time
> 1, then thread 0 executes at time 2, etc.).  Each thread has its own
> context (including a program counter).

Ah, I see.  And presumably this knowledge of synchronicity is something
that can be leveraged by the programmer for specific tasks?  Or does 
the closed pipeline mean that you have unpredictable delays that can
stall the pipeline, which can then throw off the thread lock-step?

> I'm not sure what kind of
> performance I would get in translating a single bundle at a time (or
> maybe I'm misunderstanding).

"Poor" might be a word to describe it.

> I think I'll get basic single-thread operation working first, then
> attempt multithreading when I have a spare month or so.

Good plan.


r~