[16] RFR(XS): 8248467: C2: compiler/intrinsics/object/TestClone fails with -XX:+VerifyGraphEdges

[Christian Hagedorn]

Hi

Please review the following patch:
https://bugs.openjdk.java.net/browse/JDK-8248467
http://cr.openjdk.java.net/~chagedorn/8248467/webrev.00/

The assertion is hit due to a MemBarNode whose precedence edge was set 
to NULL at [1] (result_phi_rawoop is NULL and _resproj is the precedence 
edge to a MemBarStoreStore). This is possible since JDK-8237581 [2] 
which can remove some allocations. The fix just adds this additional 
case in the assert.

Best regards,
Christian


[1] 
http://hg.openjdk.java.net/jdk/jdk/file/4a8fd81d64ba/src/hotspot/share/opto/macro.cpp#l1566
[2] https://bugs.openjdk.java.net/browse/JDK-8237581