Re: Re: Re: Re: Fwd: Re: More precise values in Analyzer

Le 16/07/2010 16:01, Joshua Warner a écrit :

[...]


> Why not tracking store ? i.e each store create a new variable.
>
>     This is the usual algorithm to convert into SSA form.
>
>
> This works fine in most cases, but this still wont work for parameters 
> because there is no "load_param" bytecode instruction in Java - all of 
> the parameters are implicitly loaded into the low local variable 
> indices before the bytecode for a method begins executing.

I don't see why it's a problem.
You just start your algorithm by creating one SSA variable by local 
variable.
I think this algorithm is described in Appel's book Modern Compiler 
Implementation in Java.


>
>
>>
>>     Even if this would work, I don't see a way to get the specific
>>     local variables index that a certain value originated in
>>     (particularly in the case of Values allocated with
>>     Interpreter.newValue(...).  Am I missing something?
>>
>>     I've read significant portions of "ASM 3.0 A Java bytecode
>>     engineering library
>>     <http://download.forge.objectweb.org/asm/asm-guide.pdf>", and I
>>     didn't see anything that could help me with this particular
>>     problem.  Do you have a certain section that you are thinking of?
>>
>>     Thanks,
>>
>>     Joshua
>
>     There is also already a llvm project that implement a basic
>     bytecode frontend:
>     https://llvm.org/svn/llvm-project/java/trunk/docs/java-frontend.txt
>
>     cheers,
>     Rémi
>
>
> Thanks, that's definitely something to look into some more; however, 
> as the generated code has to work closely with the internals of a 
> specific JVM, I expect I would have to make numerous changes to how it 
> lowers operations like virtual method calls and interface calls, as 
> well as what format it expects its objects in.  This may or may not be 
> easy.
>
> Sincerely,
>
> Joshua

cheers,
Rémi

-- 
You receive this message as a subscriber of the [email protected] mailing list.
To unsubscribe: mailto:[email protected]
For general help: mailto:[email protected]?subject=help
OW2 mailing lists service home page: http://www.ow2.org/wws