[lworld] RFR: 8364464: [lworld] GCs do not process flat arrays by chunks [v3]

[Ivan Walulya]

> Hi,
> 
> Please review this change to add Array Chunking for flatArrays with oops across the G1, Parallel, and Serial GCs
> 
> This update addresses the regression reported in [JDK-8373029](https://bugs.openjdk.org/browse/JDK-8373029).
> 
> Results after the change:
> 
> 
> jdk/bin/java BigArray 80000000
> 
> real    0m35.790s
> user    5m38.042s
> sys     0m1.666s
> 
> 
> 
> jdk/bin/java --enable-preview BigArray 80000000
> 
> real    0m18.865s
> user    2m57.155s
> sys     0m1.799s
> 
> 
> Test: Tier 1-2 with` --enable-preview`

Ivan Walulya has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains eight additional commits since the last revision:

 - Merge remote-tracking branch 'upstream/lworld' into flatArraySplits_Serial_v1
 - use uintptr_t
 - Axel Review
 - space
 - Serial-GC changes
 - Parallel Changes
 - G1 Changes
 - FlatArrayOop::oop_iterate_elements_range

-------------

Changes:
  - all: https://git.openjdk.org/valhalla/pull/2142/files
  - new: https://git.openjdk.org/valhalla/pull/2142/files/9f63e6e9..df248b32

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=2142&range=02
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=2142&range=01-02

  Stats: 22000 lines in 613 files changed: 13633 ins; 3483 del; 4884 mod
  Patch: https://git.openjdk.org/valhalla/pull/2142.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2142/head:pull/2142

PR: https://git.openjdk.org/valhalla/pull/2142