[tree-ssa] Maintaining/representing def-use/use-def information

[Chris Lattner]

On Mon, 15 Dec 2003, Daniel Berlin wrote:
> > There are ways around this, but the SSAPRE papers have several fairly
> > severe bugs and ommissions in them.  This information is not really
> > needed
> > for implementing PRE on SSA form.
> >
>
> Yes, you could do E-Path PRE, but it's harder to extend it to perform
> strength reduction or load speculation.

Yup, and FWIW, LLVM uses an e-path based formulation of PRE on SSA form.

-Chris

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