[lworld] RFR: 8349110: [lworld] Intrinsics for Unsafe.get/putFlatValue [v5]

[Quan Anh Mai]

> Hi,
> 
> This PR implements intrinsics for `Unsafe::get/putFlatValue` and enables the corresponding tests in `TestIntrinsics`.
> 
> Please kindly review, thanks very much.

Quan Anh Mai 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 six additional commits since the last revision:

 - exclude test84
 - Merge branch 'lworld' into unsafeflatvalue
 - remove -DeoptimizeALot
 - Revisit TODOs in TestIntrinsics
 - Buffer an InlineTypeNode on mismatched access
 - Implement Unsafe::flatValue accesses

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

Changes:
  - all: https://git.openjdk.org/valhalla/pull/1482/files
  - new: https://git.openjdk.org/valhalla/pull/1482/files/74378233..3327b8a2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=1482&range=04
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=1482&range=03-04

  Stats: 1743 lines in 82 files changed: 1540 ins; 18 del; 185 mod
  Patch: https://git.openjdk.org/valhalla/pull/1482.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1482/head:pull/1482

PR: https://git.openjdk.org/valhalla/pull/1482