RFR: JDK-8289551: Conversions between bit representations of half precision values and floats [v7]

[Joe Darcy]

> Initial implementation.

Joe Darcy 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 23 additional commits since the last revision:

 - Implement review feedback.
 - Merge branch 'master' into JDK-8289551
 - Implement review feedback.
 - Method rename.
 - Merge branch 'master' into JDK-8289551
 - Respond to review feedback; improve tests.
 - Add NaN test.
 - Preserve NaN sign bit.
 - Respond to review feedback.
 - Correct carry-out bug; add full binade test.
 - ... and 13 more: https://git.openjdk.org/jdk/compare/a46ba547...6afaafbb

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9422/files
  - new: https://git.openjdk.org/jdk/pull/9422/files/d54f9c94..6afaafbb

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9422&range=06
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9422&range=05-06

  Stats: 2760 lines in 105 files changed: 1365 ins; 1054 del; 341 mod
  Patch: https://git.openjdk.org/jdk/pull/9422.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9422/head:pull/9422

PR: https://git.openjdk.org/jdk/pull/9422