RFR: 8352635: Improve inferencing of Float16 operations with constant inputs [v2]

[Jatin Bhateja]

> This is a follow-up PR#22755 to improve Float16 operations inferencing.
> 
> The existing scheme to detect Float16 operations for some operations is based on pattern matching which expects to receive inputs through ConvHF2F IR, this patch extends matching to accept constant floating point inputs within the Float16 value range.
> 
> Best Regards,
> Jatin

Jatin Bhateja has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains one new commit since the last revision:

  Adding test points and some re-factoring

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Changes:
  - all: https://git.openjdk.org/jdk/pull/24179/files
  - new: https://git.openjdk.org/jdk/pull/24179/files/021009c0..4a7a519b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24179&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24179&range=00-01

  Stats: 47 lines in 3 files changed: 33 ins; 4 del; 10 mod
  Patch: https://git.openjdk.org/jdk/pull/24179.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24179/head:pull/24179

PR: https://git.openjdk.org/jdk/pull/24179