[jdk21u] RFR: 8312573: Failure during CompileOnly parsing leads to ShouldNotReachHere

[Tobias Hartmann]

Parsing of `-XX:CompileOnly=` hits a `ShouldNotReachHere` for `,` and ` ` arguments. The fix is to remove the assumption that `className` can only be null for `method_sep` because the parsing loop also exits on `,` and ` `:

https://github.com/openjdk/jdk21u/blob/384a8b85a7266b920242ea73baf578577ca588ec/src/hotspot/share/compiler/compilerOracle.cpp#L1032-L1037

Instead, a missing class name is handled as "Any" class match in all the cases.

I'm fixing this in JDK 21u because the issue was fixed in in JDK 22 as a side effect of [JDK-8027711](https://bugs.openjdk.org/browse/JDK-8027711). The VM now prints an error:


CompileOnly: An error occurred during parsing
Line: ','
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.


Thanks,
Tobias

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Commit messages:
 - 8312573: Failure during CompileOnly parsing leads to ShouldNotReachHere

Changes: https://git.openjdk.org/jdk21u/pull/19/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=19&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8312573
  Stats: 67 lines in 2 files changed: 52 ins; 11 del; 4 mod
  Patch: https://git.openjdk.org/jdk21u/pull/19.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/19/head:pull/19

PR: https://git.openjdk.org/jdk21u/pull/19