[15] RFR(XS): 8238811: C2: assert(i >= req() || i == 0 || is_Region() || is_Phi()) with -XX:+VerifyGraphEdges

[Christian Hagedorn]

Hi

Please review the following patch:
https://bugs.openjdk.java.net/browse/JDK-8238811
http://cr.openjdk.java.net/~chagedorn/8238811/webrev.00/

Not only region and phi nodes can have null data inputs but also 
arraycopy nodes (on different indices) and unlock nodes (always on the 
last index).

Thank you!

Best regards,
Christian