RFR: 8350988: Consolidate Identity of self-inverse operations [v2]

[Hannes Greule]

> subnode has multiple nodes that are self-inverse but lacking the respective optimization. ReverseINode and ReverseLNode already have the optimization, but we can deduplicate the code for all those operations.
> 
> For most nodes, the optimization is obvious. The NegF/DNodes however are worth to look at in detail imo:
> - `Float.NaN` has the same bits set as `-Float.NaN`. That means, it this specific case, the operation is a no-op anyway
> - For other values, the msb is flipped, flipping twice results in the original value again.
> 
> Similar changes could be made to the corresponding vector nodes. If you want, I can do that in a follow-up RFE.
> 
> One note: During benchmarking those changes, I ran into https://bugs.openjdk.org/browse/JDK-8307516. That means code like
> 
>         int v = 0;
>         for (int datum : data) {
>             v ^= Integer.reverseBytes(Integer.reverseBytes(datum));
>         }
>         return v;
> 
> was vectorized before but is considered "not profitable" with the changes here, causing slowdowns in such cases.

Hannes Greule 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 five additional commits since the last revision:

 - use Generators
 - after merge cleanup
 - Merge branch 'master' into involution-nodes
 - collapse impl, add more fitting nodes
 - test

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/23851/files
  - new: https://git.openjdk.org/jdk/pull/23851/files/41c555cd..b82ed237

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23851&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23851&range=00-01

  Stats: 65786 lines in 1301 files changed: 29325 ins; 24767 del; 11694 mod
  Patch: https://git.openjdk.org/jdk/pull/23851.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23851/head:pull/23851

PR: https://git.openjdk.org/jdk/pull/23851