[Help-smalltalk] Re: Dynamic compilation in GNU Smalltalk

[Paolo Bonzini]

Ludovic Courtès wrote:

> Hi,
>
> First, thank you for providing GNU Lightning.  I think it's a very
> valuable tool and it ought to be used more widely.
>
> I have a few questions about how it is used in GNU Smalltalk -- you
> might want to redirect it to some more appropriate mailing list or
> such.  Basically:  does GNU Smalltalk basically compiles bytecode to
> native code, or does it also perform specialization or some such, as in
> Psyco for instance[1]?
Yes, it specializes code for each instance, but it is used very little 
right now -- in fact, the only cases in which the methods are different are:

- if the receiver is SmallInteger

- if the method is one of the primitives as #basicAt:, #basicAt:put:, 
#basicSize, #==, #class in Object or String.

Plus, arithmetic on SmallIntegers is inlined in the method.

The code generator is mostly template-based, with some small 
optimizations to improve register allocation.

Paolo