TruffleSOM: A Smalltalk implemented with Truffle

[Doug Simon]

Hi Stefan,

What is the git command line I need to use to clone the TruffleSOM repository? When I run:

git clone https://github.com/smarr/som-java.git

I don't get the TruffleSOM sources browsable at https://github.com/smarr/som-java/tree

-Doug

On Jun 28, 2013, at 3:23 PM, Stefan Marr <java at stefan-marr.de> wrote:

> Hi:
> 
> In order to get to know the Truffle framework better, I ported SOM, a little
> Smalltalk bytecode interpreter written in Java, to Truffle.
> 
> The result is a first basic version that does not yet use any of the advanced
> features of Truffle, but is fully functional and executes tests and benchmarks:
> 
>  https://github.com/smarr/som-java/tree/TruffleSOM/master
> 
> When I was implementing it, I was wondering whether you might be interested in
> TruffleSOM as a show case for how to use Truffle. Digging through the
> implementation of SimpleLanguage and the test cases did give me only minimal
> guidance. The set of language features covered is just too minimal. Relevant
> features such as calling methods, proper calling conventions, supporting
> lexical scopes, proper usage of control-flow exceptions and so on are either
> not covered or only in the simplest variation. So, to get a better idea of how
> to use Truffle, I actually looked at FastR, but I had the feeling that using
> Truffle was only an afterthought and thus, I am not sure whether it is used
> 'idiomatically'. Furthermore, the R semantics make it rather hard to see the
> key elements.
> 
> However, if that would be interesting, I could use some feedback on the way
> Truffle is used. One example that should probably be changed is the way I
> implement lexical scopes for variable access and non-local returns. I suppose I
> should use materialized frames for that because a block/closure is holding on
> to its frame. And there are other things that could be done better, for
> instance, I am not yet supporting blocks/closures escaping from their
> activation scope, i.e., blocks that get returned as values from the method
> where they are defined.
> 
> 
> I would also like to use the chance to report a little problem, I had with the
> way the type system works. I haven't really used it yet, but I had trouble with
> the som.vmobjects.Object class clashing with java.lang.Object. That lead me to
> add a hack to the codegen to use fully qualified names for all classes with the
> simple name Object. I am sure there are more general solutions to the problem,
> but I wanted to avoid having to rename the Object class. The current patch I
> use is available here:
> 
>  https://github.com/smarr/graal/commit/12cf68632189703cb6cdcf683dc296452cded875
> 
> Another little nit is this patch:
> 
>  https://github.com/smarr/graal/commit/47437eba9b955108a1ed2cba0806d7f192fab238
> 
> I messed up the mx/env file when getting started, and found the resulting
> Python stack trace rather unpleasant.
> 
> However, while I encountered a few stumbling blocks being not familiar with
> Truffle, overall I had the feeling that it is rather pleasant to use. For
> specific questions, the javadocs and test cases typically already provide hints
> how to solve problems or how to use the API correctly. So, thanks for the nice
> framework :)
> 
> Best regards
> Stefan
> 
> -- 
> Stefan Marr
> Software Languages Lab
> Vrije Universiteit Brussel
> Pleinlaan 2 / B-1050 Brussels / Belgium
> http://soft.vub.ac.be/~smarr
> Phone: +32 2 629 2974
> Fax:   +32 2 629 3525
>