Re: 'equivTo' and locals

[Patrick LAM <plam@sable.mcgill.ca>]

On Thu, 26 Jul 2001, Stephen Andrew Neuendorffer wrote:

>
> It is fairly easy, and in fact, relatively benign to create local
> variables that have the same name and the same type.  The code
> creates valid class files, and runs fine, since the name and type
> of locals doesn't really have any semantic meaning when it comes
> to the bytecode.

Well, that's not completely true.  If you create jimple code and then you
parse the jimple code, you're out of luck.

> However, The CommonSubexpressionEliminator creates incorrect code
> when this happens, because it uses equivTo and thinks the locals
> are the same, even if they are distinct.

I've developed a patch for the CommonSubexpressionEliminator to eliminate
this behaviour.  I thought I'd mailed it to the list, but I can certainly
mail it privately to you if required.

pat