RFR(S): 8238385: CTW: C2 (Shenandoah) compilation fails with "Range check dependent CastII node was not removed"

[Roman Kennke]

Looks good, thank you!

Roman


> 
> http://cr.openjdk.java.net/~roland/8238385/webrev.00/
> 
> Barrier expansion modifies the graph in a way that causes 2 subsequent
> if to become candidate for folding as a single unsigned test. This
> causes the creation of a range check CastII at a point in the
> compilation process where none is expected to be created: they are
> removed after loop opts but as part of barrier expansion we run an extra
> pass of loop opts. The fix simply removes the ones created during
> barrier expansion if any the same way they are removed are loop opts.
> 
> Roland.
>