RFR: 8354996: Reduce dynamic code generation for a single downcall [v3]

[Chen Liang]

> Perf numbers for simple main:
> Linking of `Class::forName0` down from ~152 to ~83
> 
> For calling little color management system https://bugs.openjdk.org/browse/JDK-8313344:
> JNI: ~45
> baseline panama: ~164
> patch: ~103
> 
> Also see #24705.

Chen Liang 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:

 - Merge branch 'master' of https://github.com/openjdk/jdk into exp/ffm-lcms
 - Use more simple function descriptor
 - Simplify FFM linker warmup
 - Merge branch 'master' of https://github.com/openjdk/jdk into exp/ffm-lcms
 - Wip work trying to speed up FFM

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/24742/files
  - new: https://git.openjdk.org/jdk/pull/24742/files/dbf7799c..f762f72f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24742&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24742&range=01-02

  Stats: 46599 lines in 1266 files changed: 35620 ins; 7149 del; 3830 mod
  Patch: https://git.openjdk.org/jdk/pull/24742.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24742/head:pull/24742

PR: https://git.openjdk.org/jdk/pull/24742