KQEMU 1.3.0pre10 released - under the GPL

Posted Feb 8, 2007 0:16 UTC (Thu) by mikov (guest, #33179)
In reply to: KQEMU 1.3.0pre10 released - under the GPL by danshearer
Parent article: KQEMU 1.3.0pre10 released - under the GPL

See https://nowt.dyndns.org/ where Paul Brook has done exactly this, and I think Fabrice intends to merge Paul's code.

Very interesting. Are there any details available on the implementation of the generator ? Intermediate representation, what optimizations it performs, etc ? Or any performance benchmarks ?

I couldn't find anything relevant with Google. All I was able to find was one sentence claiming 30% improvement, which is somewhat disappointing.

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KQEMU 1.3.0pre10 released - under the GPL

Posted Feb 8, 2007 11:09 UTC (Thu) by danshearer (guest, #18686) [Link] (1 responses)

> Very interesting. Are there any details available on the implementation of
> the generator ?

Not that I know of, apart from the code.

If you have the skills, why not document what you see as you read the code? That would be helpful to people like me. I am playing with Paul's work because it addresses a problem I care about (portability, preventing me from creating internal test suites for QEMU) but so long as it works my interests lie elsewhere inside QEMU. But if there was a guided tour I'd have a look for sure.

Dan

KQEMU 1.3.0pre10 released - under the GPL

Posted Feb 8, 2007 20:12 UTC (Thu) by mikov (guest, #33179) [Link]

I think the original author is in the best position to write something like that. It shouldn't take long to describe the basic idea of what he has done - just an outline. Anyway, I think writing a guide is not so much an issue of skill, but of time ... :-(

HP's Dynamo, Intel's IA32-EL, Transmeta and others have shown that there is definite potential in re-optimizing binary code. It is possible that an advanced optimizing code generator for QEMU could even outperform native code! Of course it would have to go significantly beyond the current QEMU infrastructure and rely on dynamic recompilation, trace optimization, etc. Some more info on this subject is available here: http://www.cag.csail.mit.edu/rio/#pubs/

In any case I will definitely take a closer look at Paul Brook's work. BTW, how does it address portability ?