I would like to know if there is any news about its progress.
I cant wait to try it.

http://morphos.pl/projekt.php?projekt=16

Unfortunately life got in the way of doing MorphOS stuff for a while, so everything has been pretty much on hold this year so far, however things are looking better now.

I do realise that I'm way past my deadline already. I've dedicated this week to working on this project again, so hopefully by the end of this month I can finally show some progress.

I'm sorry to have kept you all waiting for so long.

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Thanks for the update!

Yes, thanks for the update :)

In the last couple of month I learned a bit too well myself how life can hate deadlines.

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Life loves deadlines. Especially the whooshing sound they make as they fly by.

Just an update to let you guys know that all the base work is done now. That is, all the required code is now written. What's remaining to do is then to debug the whole thing.

Unfortunately it turns out that Webkit's JIT engine suffers from a number of endian related bugs that due to the nature of JIT are rather difficult to track down, so a fair amount of debugging work is required from here to get it to actually do anything useful.

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Thanks for the update Mark.

I wish you the very best of British for the laborious task of debugging the thing. :)

Unfortuantely it turned out that the Webkit endian issued ran deep into the design of the JIT engine, so getting the issues ironed out took quite a while longer than I had expected.

The good news is that OWB+JIT is now successfully running simple Javascript programs as native PPC code. The bad news is that if I need to iron out every single endian issue, it'll take forever before I'm done. So my current plan is to try to leave some of the endian bugs intact, and instead work around them in the PPC specific part of the code. The advantage of doing it that way is that, if it works, it will take a lot less time to do. The disadvantage would be a negligible (probably less than 1%) performance loss.

Here is a phone camera shot of the first Javascript test program that successfully ran through the JIT. It's a simple page with a counter on it that increments when you move the mouse over the counter.

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Sounds like you uncovered an ants nest. Good to hear it's progressing, and look forward to seeing the benefits in Odyssey. Won't seperating out the workarounds help with (potential) future updates aswell?

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Indeed, a smaller and less intrusive change set probably has a higher chance of being accepted by the upstream Webkit project, which in turn would mean less effort to update to newer versions of Webkit.

I'm still working on my "new plan". Hopefully it will bear fruit within a few hours, and if it does, then things should progress rather rapidly from there. Fingers crossed :)

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Unfortunately I ran into some hardware issues which slowed me down a bit, however I did manage to finish that code, and it's working as expected! Besides that I've managed to fix a few bugs related to flow control and floating point arithmetics, so calculating pi in Javascript now produces the correct result :)

The goal for tomorrow is to have some simple graphical demos running. Fingers crossed!

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Great news! Hardware still suffering from the Pretorian climate?

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Brave words!
/me prepares ATan(Tan(pi/2)) test.

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Wow.

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Haha, where I am now, it's a nice 19 degrees celsius (66 fahrenheit). They call it "winter" :D

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Since both atan and tan would simply result in external function calls, this should work fine already :P However I'm probably missing a joke somewhere... ;)

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Scarf & gloves are optional then.

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Damn. Note to self: maths jokes are never funny. :P
Tan(pi/2) approaches infinity at a steep curve, and as such is very dependent upon precise values of Pi. Reversing the function tends to show up any rounding errors of the value of pi used.

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Well, it's still limited by the capabilities of IEEE double precision floats, so you won't get any better precision than what doing the equivalent in C would give you... Unless you find some big number Javascript library somewhere :)

I'm impressed with the work and the progress. This site might be good for testing the javascript capability (and handling some big numbers) http://brainwallet.org/

This might be a good test for your engine.

http://peacekeeper.futuremark.com/

OWB-JIT now renders mandelbrot correctly ;)

Excellent work !

Thanks a lot bigfoot to give info about this project !

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Nice! Any early benchmark compared to traditional interpreter ?

@bigfoot

Great work! Can't wait to try it out!

Benchmarks please

It's a bit too early for real benchmarks, as my OWB is still full of debug output that slows things down considerably, but the Mandelbrot test I'm using seems to be somewhere in the region of 5 to 10 times as fast as the interpreter. But keep in mind that this is just the 'baseline JIT'. Webkit has another level of JIT called 'DFG' that promises further speedups through eliminating runtime type checking when possible, amongst other things.

This graph was recently posted with the caption "Figure 3. Relative speed-up (higher is better) on the Richards benchmark from each of the three tiers." to a Webkit blog post. While this graph only demonstrates a specific benchmark on x86, it still gives an idea about what kind of speedups are possible.

The more interesting question will be if one has to restart Odyssey within minutes instead of hours due to WebKit/JS related memleaks anyway .... :)

@bigfoot

Do you have any plans to eventually port DFG as well?

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That's the plan, yes. But considering how deep into the design the reliance on little endian runs in Webkit's Javascript engine, I want to make sure the first level is working correctly before I go any further.