RFR(S): 8203215: IdealLoopTree::split_outer_loop leaves phi-nodes with only one input

[Vladimir Kozlov]

Yes, it is reasonable place to do IGV optimization.
Good.

Thanks 
Vladimir

> On May 15, 2018, at 2:06 AM, Nils Eliasson <nils.eliasson at oracle.com> wrote:
> 
> Hi,
> 
> I ran into an issue in the ZGC repo caused by optimizations encountering loop-phi-nodes having only one input. I tracked down the source of these to IdealLoopTree::split_outer_loop that is a part of beautify_loops.
> 
> This patch makes sure that the phis that may need a transform is processed after beautify_loops is completed, but before the loop tree is rebuilt.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8203215
> 
> Webrev: http://cr.openjdk.java.net/~neliasso/8203215/webrev.01/
> 
> Please review,
> 
> Nils
>