<i18n dev> RFR: 8373392: Replace CDS object subgraphs with @AOTSafeClassInitializer [v3]

[Ioi Lam]

> In legacy CDS, Java objects used by certain classes are computed ahead of time using "object subgraphs"
> 
> https://github.com/openjdk/jdk/blob/1bbbce75c5e68429c2a32519eb3c36d964dcdf57/src/hotspot/share/cds/heapShared.cpp#L168-L171
> 
> Examples of subgraphs:
> 
> - `java.lang.Integer$IntegerCache::cache`
> - `jdk.internal.module.ArchivedBootLayer::bootLayer`
> 
> The implementation requires special code (in both Java and C++) to be executed when a CDS archive is created or loaded. As a result, we have an execution model that's difficult to implement/extend and the behavior is hard to understand.
> 
> To move towards the AOT Cache Snapshot Model ([JDK-8365645](https://bugs.openjdk.org/browse/JDK-8365645)) we should replace the subgraphs with the use of `@AOTSafeClassInitializer`, and if necessary, `@AOTRuntimeSetup`. This will simplify the current implementation, and make it possible to extend AOT-initializations to more core classes.
> 
> Note, the use of `@AOTSafeClassInitializer` requires `-XX:+AOTClassLinking`. For the time being, we retain the old CDS object subgraph code to cover the `-XX:-AOTClassLinking` cases. Such code will be marked with comments like `/* Legacy CDS archive support (to be deprecated) */`. All future AOT creation of Java objects will be done with  `@AOTSafeClassInitializer`.

Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:

  Fixed test case -- the regexp pattern could match the stats for the subgraphs table, which now has a single entry

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Changes:
  - all: https://git.openjdk.org/jdk/pull/28736/files
  - new: https://git.openjdk.org/jdk/pull/28736/files/5497502f..306d9167

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28736&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28736&range=01-02

  Stats: 41 lines in 1 file changed: 38 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/28736.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28736/head:pull/28736

PR: https://git.openjdk.org/jdk/pull/28736