RFR: 8341512: Optimize StackMapGenerator::processInvokeInstructions [v2]

[Shaojin Wen]

> A small optimization for StackMapGenerator::processInvokeInstructions.
> 
> 1. Use local currentFrame to avoid multiple getfields
> 2. remove Util.methodTypeSymbol(NameAndTypeEntry)
> 3. Use decStack instead of popStack to reduce array access in popStack
> 4. codeSize reduced from 277 to 262

Shaojin Wen has updated the pull request incrementally with one additional commit since the last revision:

  Update src/java.base/share/classes/java/lang/classfile/attribute/EnclosingMethodAttribute.java
  
  Co-authored-by: ExE Boss <3889017+ExE-Boss at users.noreply.github.com>

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Changes:
  - all: https://git.openjdk.org/jdk/pull/21344/files
  - new: https://git.openjdk.org/jdk/pull/21344/files/ebf280ec..eea92640

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21344&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21344&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/21344.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21344/head:pull/21344

PR: https://git.openjdk.org/jdk/pull/21344