RFR: 8323183: ClassFile API performance improvements [v6]

[Adam Sotona]

> ClassFile API performance related improvements have been separated from #17121 into this PR.
> 
> These improvements are important to minimize performance regression of
> 8294961: Convert java.base/java.lang.reflect.ProxyGenerator to use the Classfile API to generate proxy classes #17121
> 
> Please review.
> 
> Thanks,
> Adam

Adam Sotona has updated the pull request incrementally with three additional commits since the last revision:

 - updated copyright year
 - reverted custom method slots counting in StackCounter
 - improved and extended GenerateStackMaps benchmarks and renamed to CodeAttributeTools

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/17306/files
  - new: https://git.openjdk.org/jdk/pull/17306/files/79394170..5f67f8c1

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17306&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17306&range=04-05

  Stats: 313 lines in 3 files changed: 132 ins; 171 del; 10 mod
  Patch: https://git.openjdk.org/jdk/pull/17306.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17306/head:pull/17306

PR: https://git.openjdk.org/jdk/pull/17306