[LLVMdev] SelectionDAG legality: isel creating cycles

[David Greene]

On Monday 22 February 2010 13:26:54 David Greene wrote:
> On Monday 22 February 2010 13:06:39 Chris Lattner wrote:
> > > Just wanted to clarify in case someone was wondering about this.
> >
> > I'm currently working in this area.  What pattern is causing the cycle?
> > Can I get a testcase?
>
> I'll see if I can generate one and file a PR.

Ah, isLegalToFold saves us on trunk.  But we lose folding due to prefetching,
which is unfortunate.

I am seeing the error with 2.5 (yes, we are upgrading!).

I guess I'll have to backport some of the isLogalToFold logic.

                                              -Dave