----- Original Message ----- 
From: "Bert Freudenberg" <bert at freudenbergs.de>
To: "The general-purpose Squeak developers list" 
<squeak-dev at lists.squeakfoundation.org>
Sent: Wednesday, October 31, 2007 10:16 AM
Subject: Re: Thoughts on a concurrent Squeak VM


> On Oct 31, 2007, at 17:57 , Rob Withers wrote:
>
>> ----- Original Message ----- From: "Andreas Raab"  <andreas.raab at gmx.de>
>> To: "The general-purpose Squeak developers list" <squeak- 
>> dev at lists.squeakfoundation.org>
>> Sent: Wednesday, October 31, 2007 9:37 AM
>> Subject: Re: Thoughts on a concurrent Squeak VM
>>
>>
>>> Rob Withers wrote:
>>>> What about using C++?  There would be some degradation of  performance. 
>>>> However, there would be the benefit of structuring  the VM classes, of 
>>>> not having to add VM as an argument  everywhere, and it may even be 
>>>> possible to subclass Thread so we  know where the thread-local storage 
>>>> is.
>>>
>>> For the VM internally, I don't really care. Since this is  generated 
>>> code there is really no difference to me. For plugins it  is not 
>>> feasible to use C++ since name mangling not standardized so  you can't 
>>> link reliably to C++ APIs.
>>
>> That's true that it's internal to the VM so it shouldn't matter.  I 
>> suppose the benefi of structuring the classes was more of an in  image 
>> issue with me. Even using C, we could separate off the  primitives into a 
>> Primitives class and compile with ObjectMemory,  Interpreter, and 
>> Primitives so they are all generated in the same  file.  Then we would 
>> just need to make sure the  InterpreterSimulator knew about the 
>> Primitives class.  The same  issue as would apply if ObjectMemory and 
>> Interpreter were no longer  part of the same hierarchy.
>>
>> It makes sense that primitives would have a problem with name  mangling, 
>> so named primitives can't be in C++ classes...indexed  could be, though, 
>> as long as the primitive table were initialized  with the mangled names.
>
> I don't see any point in switching to C++.

I'm convinced.  It was a little hard to let go since I like an OO 
representation, but as Andraes observed, the VM being generated means I 
don't really need to look at it too closely.  For me it is more about the 
class representation of the VM in the image.  Interpreter is a busy class 
and some of it's methods could be broken out in separate Squeak classes.

cheers,
Rob