RFR: Fix aarch64 after merge

[Aleksey Shipilev]

On 04/25/2018 12:35 AM, Roman Kennke wrote:
> This moves code around in aarch64 to account for yesterday merge.
> 
> http://cr.openjdk.java.net/~rkennke/fix-merge-aarch64/webrev.00/

barrierSetAssembler_aarch64.cpp: resolve_* deserve a comment that they are deliberately no-op.

> There are two backportable changes that fix actual issues:
> - c1_LIRGenerator.cpp to fix assert in TestSelectiveBarrierFlags.java
> makes C1 barrier generation more consistent with interpreter and other
> places

This should be RFR-ed separately for backports. I think the reason we called into shenandoah_*_impl
methods is that we could still have a storeval barrier even if common WB/RBs are disabled. This
patch stops emitting storevals with -XX:-ShWB -XX:-ShRB -XX:+ShSVB, when it really should. Is there
an assert you are facing somewhere without this patch?

> - write-barrier checking for EVACUATION | PARTIAL | TRAVERSAL instead of
> just EVACUATION fixes partial+traversal modes

Please RFR that fix for sh/jdk10 separately?

Thanks,
-Aleksey