Bulk backports to sh/jdk8

[Aleksey Shipilev]

On 4/23/20 4:06 PM, Roman Kennke wrote:
> Changesets:
> http://cr.openjdk.java.net/~rkennke/backport-shjdk8-2020-04-23/changesets.txt
> 
> Full webrev:
> http://cr.openjdk.java.net/~rkennke/backport-shjdk8-2020-04-23/webrev.00/
> 
> Testing: hotspot_gc_shenandoah (x86, aarch64)

*) Please grep for leftover ShenandoahKeepAliveBarrier in source code? 8u might have some surprises
there, for example in x86_32 parts;

*) Indent is a bit off in shenandoahConcurrentMark.cpp here:

 220   ShenandoahSATBBufferClosure* _satb_cl;
 221   OopClosure*            const _cl;
 222   MarkingCodeBlobClosure*              _code_cl;

*) Not related to this backport. But looking at for example TestClassLoaderLeak.java, it looks to me
IU can use the same bundle of heuristics like normal mode uses. Probably something to fix in
upstream and let it trickle?

 125         String[][][] modeHeuristics = new String[][][] {
 126              {{"normal"},  {"adaptive", "compact", "static", "aggressive"}},
 127              {{"iu"},      {"adaptive", "aggressive"}},
 128              {{"passive"}, {"passive"}}

*) In new tests, does it not complain about vm.gc.Shenandoah and vm.graal.enabled flags? IIRC, not
all test flags are available in 8u, and that's why test backports remove those lines...

Otherwise good!

-- 
Thanks,
-Aleksey