Parrot VM

> The site says that
>
> "Parrot is a virtual machine aimed at running all dynamic languages.".
>
> but I don't know anything about VM so this sounds to me a bit like black
> magic.
>
> Is there something in the squeak vm that is specific to the way
> smalltalk works or a generic virtual machine (maybe with a upper layer
> understanding Smalltalk specifics) can be used.
>
> Thanks for the answers
>
> --
> Miguel Cobá
> http://miguel.leugim.com.mx
>
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

>
> On 20 Jan 2010, at 06:12, Miguel Enrique Cobá Martinez wrote:
>
>> Parrot has just been released:
>> http://www.parrot.org/news/2010/Parrot-2.0.0
>>
>> I would like to know, from the VM experts from the community, if this VM
>> can be used to run Smalltalk.
> Well, as someone mentioned, there seems to be Smalltalk implementation...
>
> But, probably it is hard to get it fast.
> Parrot uses a very unique approach.
> Actually, they try to provide a language runtime for all kinds of languages, and the right tools to build them: http://www.linux-mag.com/cache/7373/1.html
>
> Eliot mentioned primitives, well, there is no concept of a primitive in Parrot.
> Instead, they have a unification of bytecodes and primitives. The idea is, to give you the tools to develop the bytecode you need for your language, which can be loaded dynamically during execution.
> It will be interesting to see, how they can get their JIT fast with this strategy.
>
> Best
> Stefan
>
>
>> The site says that
>>
>> "Parrot is a virtual machine aimed at running all dynamic languages.".
>>
>> but I don't know anything about VM so this sounds to me a bit like black
>> magic.
>>
>> Is there something in the squeak vm that is specific to the way
>> smalltalk works or a generic virtual machine (maybe with a upper layer
>> understanding Smalltalk specifics) can be used.
>>
>> Thanks for the answers
>>
>> --
>> Miguel Cobá
>> http://miguel.leugim.com.mx
>>
>>
>> _______________________________________________
>> Pharo-project mailing list
>> [hidden email]
>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>
> --
> Stefan Marr
> Software Languages Lab
> Vrije Universiteit Brussel
> Pleinlaan 2 / B-1050 Brussels / Belgium
> http://soft.vub.ac.be/~smarr
> Phone: +32 2 629 3956
> Fax:   +32 2 629 3525
>
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

> stefan
>
> do you know how this is linked with pypy?
>
> Stef
>
> On Jan 20, 2010, at 8:50 AM, Stefan Marr wrote:
>
>>
>> On 20 Jan 2010, at 06:12, Miguel Enrique Cobá Martinez wrote:
>>
>>> Parrot has just been released:
>>> http://www.parrot.org/news/2010/Parrot-2.0.0
>>>
>>> I would like to know, from the VM experts from the community, if this VM
>>> can be used to run Smalltalk.
>> Well, as someone mentioned, there seems to be Smalltalk implementation...
>>
>> But, probably it is hard to get it fast.
>> Parrot uses a very unique approach.
>> Actually, they try to provide a language runtime for all kinds of languages, and the right tools to build them: http://www.linux-mag.com/cache/7373/1.html
>>
>> Eliot mentioned primitives, well, there is no concept of a primitive in Parrot.
>> Instead, they have a unification of bytecodes and primitives. The idea is, to give you the tools to develop the bytecode you need for your language, which can be loaded dynamically during execution.
>> It will be interesting to see, how they can get their JIT fast with this strategy.
>>
>> Best
>> Stefan
>>
>>
>>> The site says that
>>>
>>> "Parrot is a virtual machine aimed at running all dynamic languages.".
>>>
>>> but I don't know anything about VM so this sounds to me a bit like black
>>> magic.
>>>
>>> Is there something in the squeak vm that is specific to the way
>>> smalltalk works or a generic virtual machine (maybe with a upper layer
>>> understanding Smalltalk specifics) can be used.
>>>
>>> Thanks for the answers
>>>
>>> --
>>> Miguel Cobá
>>> http://miguel.leugim.com.mx
>>>
>>>
>>> _______________________________________________
>>> Pharo-project mailing list
>>> [hidden email]
>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>>
>> --
>> Stefan Marr
>> Software Languages Lab
>> Vrije Universiteit Brussel
>> Pleinlaan 2 / B-1050 Brussels / Belgium
>> http://soft.vub.ac.be/~smarr
>> Phone: +32 2 629 3956
>> Fax:   +32 2 629 3525
>>
>>
>> _______________________________________________
>> Pharo-project mailing list
>> [hidden email]
>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

>>>>>> "Randal" == Randal L Schwartz <[hidden email]> writes:
>
> Randal> Parrot's GC suffers from having many different kinds of mixed objects.
>
> Randal> http://wknight8111.blogspot.com/2010/01/boehm-in-parrot.html
>
> And worse, having untyped data blobs on a stack... that's probably the worst
> thing there.
>
> If you can't tell what live pointers you have for sure, you can't GC, and if
> you can't GC reliably, you lose.

>
> --
> Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
> <[hidden email]> <URL:http://www.stonehenge.com/merlyn/>
> Smalltalk/Perl/Unix consulting, Technical writing, Comedy, etc. etc.
> See http://methodsandmessages.vox.com/ for Smalltalk and Seaside discussion
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>

> You mean how their approaches compare? (I would guess, there is no direct involvement of people in both projects.)
>
> PyPy is a generator approach, your language specification i.e. the interpreter is used
> to generate a VM.
> You use a high-level language i.e. RPython to implement a classic interpreter, which is then transformed by a powerful tool-chain to your C implementation (and a JIT). Stuff like GC is just generated for you.
> The result is one specific VM, which is generated for your language.
>
>
> With Parrot it is much like with a classic VM like JVM or CLR/.NET.
> You are using one existing VM.
> Language developers use the Parrot Assembly language (PASM) or the Parrot
> Intermediate Representation (PIR) which can then be compiled to the bytecode set.
> Furthermore, they can extend the bytecode set with their own instructions (primitives).
> So, you are basically compiling your target language while using all the runtime features of the Parrot VM. So, here the 'power' is in the VM, not in a transformation tool chain.
>
> Best
> Stefan
>
>
>
> On 20 Jan 2010, at 09:02, Stéphane Ducasse wrote:
>
>> stefan
>>
>> do you know how this is linked with pypy?
>>
>> Stef
>>
>> On Jan 20, 2010, at 8:50 AM, Stefan Marr wrote:
>>
>>>
>>> On 20 Jan 2010, at 06:12, Miguel Enrique Cobá Martinez wrote:
>>>
>>>> Parrot has just been released:
>>>> http://www.parrot.org/news/2010/Parrot-2.0.0
>>>>
>>>> I would like to know, from the VM experts from the community, if this VM
>>>> can be used to run Smalltalk.
>>> Well, as someone mentioned, there seems to be Smalltalk implementation...
>>>
>>> But, probably it is hard to get it fast.
>>> Parrot uses a very unique approach.
>>> Actually, they try to provide a language runtime for all kinds of languages, and the right tools to build them: http://www.linux-mag.com/cache/7373/1.html
>>>
>>> Eliot mentioned primitives, well, there is no concept of a primitive in Parrot.
>>> Instead, they have a unification of bytecodes and primitives. The idea is, to give you the tools to develop the bytecode you need for your language, which can be loaded dynamically during execution.
>>> It will be interesting to see, how they can get their JIT fast with this strategy.
>>>
>>> Best
>>> Stefan
>>>
>>>
>>>> The site says that
>>>>
>>>> "Parrot is a virtual machine aimed at running all dynamic languages.".
>>>>
>>>> but I don't know anything about VM so this sounds to me a bit like black
>>>> magic.
>>>>
>>>> Is there something in the squeak vm that is specific to the way
>>>> smalltalk works or a generic virtual machine (maybe with a upper layer
>>>> understanding Smalltalk specifics) can be used.
>>>>
>>>> Thanks for the answers
>>>>
>>>> --
>>>> Miguel Cobá
>>>> http://miguel.leugim.com.mx
>>>>
>>>>
>>>> _______________________________________________
>>>> Pharo-project mailing list
>>>> [hidden email]
>>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>>>
>>> --
>>> Stefan Marr
>>> Software Languages Lab
>>> Vrije Universiteit Brussel
>>> Pleinlaan 2 / B-1050 Brussels / Belgium
>>> http://soft.vub.ac.be/~smarr
>>> Phone: +32 2 629 3956
>>> Fax:   +32 2 629 3525
>>>
>>>
>>> _______________________________________________
>>> Pharo-project mailing list
>>> [hidden email]
>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>>
>>
>> _______________________________________________
>> Pharo-project mailing list
>> [hidden email]
>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>
> --
> Stefan Marr
> Software Languages Lab
> Vrije Universiteit Brussel
> Pleinlaan 2 / B-1050 Brussels / Belgium
> http://soft.vub.ac.be/~smarr
> Phone: +32 2 629 3956
> Fax:   +32 2 629 3525
>
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

>
>
> 2010/1/19 Miguel Enrique Cobá Martinez <[hidden email]>
>         Parrot has just been released:
>         http://www.parrot.org/news/2010/Parrot-2.0.0
>        
>         I would like to know, from the VM experts from the community,
>         if this VM
>         can be used to run Smalltalk.
>         The site says that
>        
>         "Parrot is a virtual machine aimed at running all dynamic
>         languages.".
>        
>         but I don't know anything about VM so this sounds to me a bit
>         like black
>         magic.
>        
>         Is there something in the squeak vm that is specific to the
>         way
>         smalltalk works or a generic virtual machine (maybe with a
>         upper layer
>         understanding Smalltalk specifics) can be used.
>
>
> The four things that most distinguish Smalltalk VMs from most others
> are the bytecode and primitives set, contexts, immediate objects and
> the class hierarchy with each class having a method dictionary.
>
>
> The method lookup mechanism that searches the class hierarchy has
> traditionally been part of the VM but in a well-modularised VM one
> could imagine adding it on as an extra (*1).
>
>
> Immediate objects are of course SmallInteger (a.k.a. fixnums) and in
> some implementations Character and SmallDouble.  They're the
> implementation encoding value objects within a pointer so that these
> values can be synthesized without object allocation.  To be a
> Smalltalk these must be objects to whose classes you can add methods,
> and pragmatically they need to be space and time efficient.  You can
> implement them as boxed objects but performance will be poor.  You
> can't implement them as e.g. Java integers without a lot of
> difficulty; they need to be objects.  A well-factored VM may well
> allow one to implement some immediate types; I would be surprised if
> Parrot didn't have support for fixnums.
>
>
> Contexts are the most distinctive features of Smalltalk
> implementations.  Few languages have a reification of method/function
> activation.  I doubt very much that Parrot supports anything like
> contexts.  One can attempt to do without them, but then lots of the
> exception system is in the VM and there are major restrictions
> (Seaside's continuations must be implemented differently, the debugger
> needs to be reimplemented, persisting processes is difficult, etc,
> etc).  All this is possible (VisualAge doesn't have contexts) but for
> Squeak and VisualWorks eliminating contexts is a lot of work.
>
>
> Finally the bytecode and primitive set, encapsulated in methods, are
> pretty distinctive.  These are the target of the compiler and known to
> the image indirectly by the debugger, by the browsing functions
> (senders scans methods bytecode, inst var refs scans bytecode, etc),
> and so on.  So if a VM specifies the bytecode set, rather than allows
> one to specify one's own there is a lot of work involved in targeting
> that VM.
>
>
> In practice none of these four features is fixed.  One wants to be
> able to evolve the implementation.  My closures implementation adds a
> few bytecodes, a few primitives and changes how MethodContext works
> (to support block activations; BlockContext is history).  But these
> are small changes from Squeak and, clearly, support existing Squeak
> semantics with relatively little work.  Targetting Parrot is likely to
> require much more effort.
>
>
> primitives are a can of worms.  For example, does the VM allow one to
> enumerate all instances of a class?  This is great for doing instance
> mutation when a class definition changes, but many VMs will disallow
> this kind of thing on security grounds. You can always try and do
> without but at what stage does it no longer remain Smalltalk?
>  Smalltalk is more than syntax.  
>
>
> And of course a different VM may be perfectly acceptable for certain
> kinds of deployed applications.  One may live with the restrictions
> involved in compiling Smalltalk to JavaScript in return for browser
> ubiquity.
>
>
> So you've asked an interesting question that overs a large space of
> implementation approaches and levels of effort.  In my experience you
> never know how hard or easy something really is until you try doing
> it.
>
>
>
>
> *1 and some VMs such as the Mushroom Smalltalk VM and Ian's Cola have
> virtualized method lookup, so it doesn't have to be part of the core
> and so is the least distinctive of the three features.
>
>

> You mean how their approaches compare? (I would guess, there is no direct involvement of people in both projects.)
>
> PyPy is a generator approach, your language specification i.e. the interpreter is used
> to generate a VM.
> You use a high-level language i.e. RPython to implement a classic interpreter, which is then transformed by a powerful tool-chain to your C implementation (and a JIT). Stuff like GC is just generated for you.
> The result is one specific VM, which is generated for your language.
>
>
> With Parrot it is much like with a classic VM like JVM or CLR/.NET.
> You are using one existing VM.
> Language developers use the Parrot Assembly language (PASM) or the Parrot
> Intermediate Representation (PIR) which can then be compiled to the bytecode set.
> Furthermore, they can extend the bytecode set with their own instructions (primitives).
> So, you are basically compiling your target language while using all the runtime features of the Parrot VM. So, here the 'power' is in the VM, not in a transformation tool chain.
>
> Best
> Stefan
>

>
>
> On 20 Jan 2010, at 09:02, Stéphane Ducasse wrote:
>
> > stefan
> >
> > do you know how this is linked with pypy?
> >
> > Stef
> >
> > On Jan 20, 2010, at 8:50 AM, Stefan Marr wrote:
> >
> >>
> >> On 20 Jan 2010, at 06:12, Miguel Enrique Cobá Martinez wrote:
> >>
> >>> Parrot has just been released:
> >>> http://www.parrot.org/news/2010/Parrot-2.0.0
> >>>
> >>> I would like to know, from the VM experts from the community, if this VM
> >>> can be used to run Smalltalk.
> >> Well, as someone mentioned, there seems to be Smalltalk implementation...
> >>
> >> But, probably it is hard to get it fast.
> >> Parrot uses a very unique approach.
> >> Actually, they try to provide a language runtime for all kinds of languages, and the right tools to build them: http://www.linux-mag.com/cache/7373/1.html
> >>
> >> Eliot mentioned primitives, well, there is no concept of a primitive in Parrot.
> >> Instead, they have a unification of bytecodes and primitives. The idea is, to give you the tools to develop the bytecode you need for your language, which can be loaded dynamically during execution.
> >> It will be interesting to see, how they can get their JIT fast with this strategy.
> >>
> >> Best
> >> Stefan
> >>
> >>
> >>> The site says that
> >>>
> >>> "Parrot is a virtual machine aimed at running all dynamic languages.".
> >>>
> >>> but I don't know anything about VM so this sounds to me a bit like black
> >>> magic.
> >>>
> >>> Is there something in the squeak vm that is specific to the way
> >>> smalltalk works or a generic virtual machine (maybe with a upper layer
> >>> understanding Smalltalk specifics) can be used.
> >>>
> >>> Thanks for the answers
> >>>
> >>> --
> >>> Miguel Cobá
> >>> http://miguel.leugim.com.mx
> >>>
> >>>
> >>> _______________________________________________
> >>> Pharo-project mailing list
> >>> [hidden email]
> >>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
> >>
> >> --
> >> Stefan Marr
> >> Software Languages Lab
> >> Vrije Universiteit Brussel
> >> Pleinlaan 2 / B-1050 Brussels / Belgium
> >> http://soft.vub.ac.be/~smarr
> >> Phone: +32 2 629 3956
> >> Fax:   +32 2 629 3525
> >>
> >>
> >> _______________________________________________
> >> Pharo-project mailing list
> >> [hidden email]
> >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
> >
> >
> > _______________________________________________
> > Pharo-project mailing list
> > [hidden email]
> > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>