[master] RFR: Merge jdk:jdk-25+21 [v2]

[Roman Kennke]

> As title says

Roman Kennke has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains two new commits since the last revision:

 - 8347711: [Lilliput] Parallel GC support for compact identity hashcode
   
   Reviewed-by: stuefe
 - 8347710: [Lilliput] Implement 4 byte headers
   
   Reviewed-by: stuefe

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Changes:
  - all: https://git.openjdk.org/lilliput/pull/198/files
  - new: https://git.openjdk.org/lilliput/pull/198/files/f12d5cd5..cab0431b

Webrevs:
 - full: Webrev is not available because diff is too large
 - incr: https://webrevs.openjdk.org/?repo=lilliput&pr=198&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/lilliput/pull/198.diff
  Fetch: git fetch https://git.openjdk.org/lilliput.git pull/198/head:pull/198

PR: https://git.openjdk.org/lilliput/pull/198