[13] RFR(S): 8224658: Unsafe access C2 compile fails with assert(flat != TypePtr::BOTTOM) failed: cannot alias-analyze an untyped ptr: adr_type = NULL

[Tobias Hartmann]

Hi,

please review the following patch:
https://bugs.openjdk.java.net/browse/JDK-8224658
http://cr.openjdk.java.net/~thartmann/8224658/webrev.00/

We hit an assert in alias analysis when compiling an unsafe off-heap access intrinsic with zero
address. We should simply bail out in this case because if that code is ever executed, it will crash
the VM anyway.

Thanks to Aleksey for reporting the issue and providing the test case.

Best regards,
Tobias