[lworld+vector] RFR: 8314980: [lworld+vector] consider scalarization conditions during ciMultiField creation. [v5]

[Jatin Bhateja]

> Patch adds a new API _ciEnv::is_multifield_scalarized_, to scalarize multifield (ciField[s]) in case target vector cannot accommodate multifield bundle size, else it creates a hierarchical structure ciMultiField and expose entire multifield bundle as one field to C2 compiler.
> 
> This cleans up special handling done in C2 compiler, ci field query APIs and object reconstruction handling  at SafePoint.
> 
> Please review and share your feedback.
> 
> 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 five commits:

 - Merge branch 'lworld+vector' of http://github.com/openjdk/valhalla into JDK-8314980
 - Removing transiant flag.
 - Restricting population of multifield bundle size and setting _is_multifield_base to only ciMultifield objects.
 - Remove unused function declaration.
 - 8314980: [lworld+vector] consider scalarization conditions during ciMultiField creation.

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Changes: https://git.openjdk.org/valhalla/pull/918/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=918&range=04
  Stats: 147 lines in 9 files changed: 31 ins; 78 del; 38 mod
  Patch: https://git.openjdk.org/valhalla/pull/918.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/918/head:pull/918

PR: https://git.openjdk.org/valhalla/pull/918