[8u] RFR for JDK-8134918 - C2: Type speculation produces mismatched unsafe accesses

[Shafi Ahmad]

Hi All,

Please review the backport of JDK-8134918 - C2: Type speculation produces mismatched unsafe accesses to jdk8u-dev.

Please note that backport is not clean and the conflict is due to:
http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/9108fab781a4#l5.165

 Getting debug build failure because of: 
http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/9108fab781a4#l5.155

The above changes are done under bug# 'JDK-8136473: failed: no mismatched stores, except on raw memory: StoreB StoreI' which is not back ported to jdk8u and the current backport is on top of above change.
 
 Please note that I am not sure if there is any dependency between these two changesets.

open webrev: http://cr.openjdk.java.net/~shshahma/8134918/webrev.00/
jdk9 bug link: https://bugs.openjdk.java.net/browse/JDK-8134918
jdk9 changeset: http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/79dae2cd00ef

testing: Passes JPRT, jtreg not completed 

Regards,
Shafi