Re: Soot 2.0.0 info request

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

On Thu, 8 May 2003, Ondrej Lhotak wrote:

> > >- SSA-Jimple. Really, this time.
> > Have the optimisations converted to use Jimple-SSA?
>
> I don't think we planned to convert the existing optimizations to SSA.
> We mainly just wanted to provide SSA to allow people who want to write
> new optimizations to use SSA if they want (and to optionally use it
> as an input to Spark). But, the SSA is very similar to Jimple, so it
> shouldn't be too hard to convert the existing optimizations to it.
> I think Navin has implemented at least some basic SSA optimizations,
> so those will be included.

To expand on Navin and Ondrej's messages, the fundamental Soot
representation is still going to be Jimple.  Those who'd like SSA form can
use Shimple (SSA-Jimple), but I don't see any benefit from converting our
current optimizations to SSA.  Remember that it's also a hassle to
maintain SSA form throughout transformations (often you have to rebuild
the SSA form, I understand -- I've never used SSA form myself, actually),
and that Jimple already provides many of the benefits of true SSA form.

I have the feeling that people often write optimizations for SSA form
because it's there, but that it doesn't actually give them any benefit.

pat