URGENT: RFR: [BACKOUT] fix for JDK-8166188

[Kim Barrett]

looks good.

> On Feb 16, 2017, at 2:21 PM, Daniel D. Daugherty <daniel.daugherty at oracle.com> wrote:
> 
> Greetings,
> 
> Sending this backout code review to the same aliases used for:
> 
>    JDK-8166188 G1 Needs pre barrier on dereference of weak JNI handles
>    https://bugs.openjdk.java.net/browse/JDK-8166188
> 
> more as a heads up that JDK-8166188 might be getting backed out.
> 
> I only need reviews from Kim and Jesper.
> 
> Doing a contingent backout of Kim's fix for the above due to some
> unexpected test failures with some JDK tests:
> 
> JDK-8175085 8166188 causes JDK test failures
> https://bugs.openjdk.java.net/browse/JDK-8175085
> 
> JDK-8175086 [BACKOUT] fix for JDK-8166188
> https://bugs.openjdk.java.net/browse/JDK-8175086
> 
> 
> Webrev URL: http://cr.openjdk.java.net/~dcubed/8175086-webrev/0-jdk9-hs/
> 
> 
> I used "hg backout 3bc68ff68250" which created a child
> changeset of Kim's:
> 
> changeset:   12639:3bc68ff68250
> user:        kbarrett
> date:        Wed Feb 15 22:19:13 2017 -0500
> summary:     8166188: G1 Needs pre barrier on dereference of weak JNI handles
> 
> The backout changeset:
> 
> changeset:   12644:ee34d6aabf5f
> parent:      12639:3bc68ff68250
> user:        dcubed
> date:        Thu Feb 16 10:41:19 2017 -0800
> summary:     8175086: [BACKOUT] fix for JDK-8166188
> 
> and then I used "hg merge" to merge with current tip.
> This was a "branch" merge with no conflicts.
> 
> 
> Sanity checks:
> 
> - The parent of Kim's changeset is:
> 
>  changeset:   12638:35db0413819a
>  user:        roland
>  date:        Wed Feb 15 17:26:37 2017 -0800
>  summary:     8174164: SafePointNode::_replaced_nodes breaks with irreducible loops
> 
> - hg diff -r 35db0413819a -r ee34d6aabf5f
> 
>  shows no output so the backout is clean.
> 
> - $ wc -l files.list
>      37 files.list
> 
> - $ hg diff -r 35db0413819a -r tip `cat files.list`
> 
>  shows no output so the merge with the tip is clean.
> 
> Thanks, in advance, for reviews from Jesper and Kim!!
> 
> Dan