[lworld] RFR: 8348607: [lworld] Calls to Unsafe.getValue() / Unsafe.putValue() must be updated [v2]

[Chen Liang]

> Core libraries counterpart of #1336.
> 
> This requires MemberName to fetch more information in initialization. A new int high flag field is added, in anticipation to a merger with the regular int flag field in the future. Currently, directly migrating the flags field to long is too impactful to the whole codebase.
> 
> Also 8348680 is addressed as well; it's some minor updates to make the null checks specific to references VH.
> 
> Testing: test/jdk/java/lang/invoke

Chen Liang 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 seven additional commits since the last revision:

 - Completely trust the value stored in fields (checked by verifier)
 - Merge branch 'lworld' of https://github.com/openjdk/valhalla into fix/vh-layout
 - Fix TestIntrinsics, safety remarks
 - Fix DMH too
 - Remove redundant checks for missing locations
 - New field in MemberName for now
 - Adapt layouts stage 1 (need to store in MemberName)

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

Changes:
  - all: https://git.openjdk.org/valhalla/pull/1340/files
  - new: https://git.openjdk.org/valhalla/pull/1340/files/1c08852b..a06cb9dc

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=1340&range=01
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=1340&range=00-01

  Stats: 82602 lines in 1449 files changed: 37468 ins; 38902 del; 6232 mod
  Patch: https://git.openjdk.org/valhalla/pull/1340.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1340/head:pull/1340

PR: https://git.openjdk.org/valhalla/pull/1340