RFR: 2018-03-19 (2), Bulk backports to sh/jdk10

[Zhengyu Gu]

Good to me.

-Zhengyu

On 03/19/2018 01:40 PM, Aleksey Shipilev wrote:
> http://cr.openjdk.java.net/~shade/shenandoah/backports/jdk10-20180319-2/webrev.01/
> 
> We have done a few trivial fixes today, and those fixes do not need to wait another backport cycle.
> Current sh/jdk should pass the first round of nightly testing in a few hours.
> 
> 094fd848894c: [backport] Remove runtime storeval barrier
> 06ccceb9e78c: [backport] Rewire control loop to avoid double cleanup work
> a295f6a1aa2f: [backport] Excessive asserts in marked_object_iterate
> 1c7331519023: [backport] Added missing header file for non-PCH build
> 685f5911964e: [backport] Remove unnecessary write-barrier
> a1665e6feb5d: [backport] Provide non-taxable allocation slack at the beginning of the cycle
> 
> Testing: hotspot_gc_shenandoah {fastdebug|release}
> 
> Thanks,
> -Aleksey
>