RFR: 8354996: Reduce dynamic code generation for a single downcall

[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.

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Commit messages:
 - Merge branch 'master' of https://github.com/openjdk/jdk into exp/ffm-lcms
 - Wip work trying to speed up FFM

Changes: https://git.openjdk.org/jdk/pull/24742/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24742&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8354996
  Stats: 141 lines in 7 files changed: 123 ins; 0 del; 18 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