Re: bug in generating variable names

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

Hi Florin,

On Fri, 8 Jun 2001, Florin Mateoc wrote:

> void
> offsetToPointer(soot.coffi.ByteCode) and public
> soot.coffi.Instruction[]
> branchpoints(soot.coffi.Instruction)) - in which a
> variable called $cseTemp0 was declared twice (in the
> first case as two different types).

This is definitely a bug in my code.  I know how to fix it and I'll try to
get to it tonight.

The common subexpression elimination phase is a bit broken when you read
in the local variable names for Jimple.  Creating bytecode is fine,
because the local names are not written, but the Jimple created is invalid
in this context.

[Common subexpression elimination is when you have e.g.

   x = y + z;
   a = y + z;

The expression 'y + z' is common to the two statements and needs only be
done once.  So you can write instead,

   $cseTmp0 = y + z;
   x = $cseTmp0;
   a = $cseTmp0;]

pat