On Fri, Mar 04, 2011 at 10:29:05AM -0500, Dimitry Golubovsky wrote:

Hi,

G??ran Krampe wrote:

...or we need to get Squeak running inside/on-top-of Dalvik somehow.

Weird ideas: - PotatoSqueak is a port of the Squeak VM to java. Run that on Dalvik and hey... - PySqueak using Pypy could probably generate a fast Squeak VM running in java bytecode which possibly also could be run on Dalvik.

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Well the original discussion on the Squeak ML declined into the OLPC issues (back to Intel that is ;)

Let's continue here.

Thanks for the hints, I looked into these projects, but:

Potato Squeak (JSqueak) doesn't seem alive. I tried to run it on my PC with some recent Java (don't remember which version, same as I use to compile Android stuff). Very slow, crashed all the time. Plus image version is 2.x ...

PySqueak seems like the repo is gone. Also, it's old too.

Anyway, wrt translation of Squeak/Pharo VM to Java. How much labor would it take to change VMMaker so it generates Java code instead of C? Given some similarity between the two languages syntax?

I think this is a perfectly reasonable thing to consider. There is of course a C code generator already in place in VMMaker, and there is no reason that a Java code generator could not be written. Matched up with some support code written in Java, the result would in principle be a VM written entirely in Java with no clib calls, FFI, JNI, etc.

I do not know what the resulting performance would be, and there is no good way to really know without trying it. But it might very well be good enough to produce a usable VM. My guess, based on absolutely no data whatsoever, is that such a VM might run perhaps 2 or 3 times slower than a standard interpreter VM.

I note that the C VMs gain a lot of their performance through the C code inlining performed by the Slang translation (which is amazingly effective by the way). I don't know if similar optimizations would apply to a Java implementation, but it seems possible that a decent Java generator with inlining might produce acceptable results.

I need to move on with the native port because my endpoint is in a concrete application rather than the port itself. But would anyone be interested in adjusting VMMaker?

If someone writes the Java code generator, then I would be happy to work on adjusting VMMaker to use it (and I'm sure others will help also). I'm not offering to write the code generator, but I think it would be great if someone wants to give it a try.

Dave