[Newcompiler] Re: NewCompiler-ms.273.mcz

[Klaus D. Witzel]

> - Add a more powerfull way for comparing compiled method
...
>
> Article:
> * http://www.squeaksource.com/NewCompiler.html
>
> Download:
> * http://www.squeaksource.com/NewCompiler/NewCompiler-ms.273.mcz

Hi Math,

the same primitive can be used by many methods but with different fallback  
code (in case the primitive fails). This so can make two methods unequal.  
I'd suggest to eliminate the check for

(self primitive > 0 and: [self primitive = method primitive])
		ifTrue:[^true].

Now since comparision of primitive numbers was formerly subsummed by

self header = method header ifFalse: [^false].

, I'd suggest to put primitive number comparision back as

  self primitive = method primitive
		ifFalse: [^false].

Also,

  self initialPC to: self endPC do:

was formerly guarded by

  self size = method size ifFalse: [^false].

Without such a guard, it's not impossible that you compare elements which  
are not bytecode.

Last but not least: comparing the literals must parallel the way the  
compiler compares the literals, see call sites of #addLiteral:, i.e.  
#pushLiteral: in BytecodeGenerator. With other words, not using #= for  
literal comparision but instead use #literalEqual:.

For the case of float literal comparision (which should be done by Float  
itself in its override of #literalEqual:) I'd suggest to ask the Squeak  
community about their opinion, their use cases and their numerical  
tolerance.

As always, I'm open to critique :)

/Klaus