[lworld+fp16] RFR: Merge lworld [v2]

[Jatin Bhateja]

> Merge latest changes from lworld.
> 
> FP16 specific tests and tier1 regressions are clean.
> 
> Best Regards,
> Jatin

Jatin Bhateja has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains four commits:

 - Merge branch 'lworld' of http://github.com/openjdk/valhalla into merge_lworld_to_fp16
 - [lworld+fp16] Merge lworld
 - 8308363: Initial compiler support for FP16 scalar operations.
   
   Reviewed-by: sviswanathan
 - Merge lworld

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Changes: https://git.openjdk.org/valhalla/pull/974/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=974&range=01
  Stats: 1548 lines in 41 files changed: 1506 ins; 3 del; 39 mod
  Patch: https://git.openjdk.org/valhalla/pull/974.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/974/head:pull/974

PR: https://git.openjdk.org/valhalla/pull/974