[jdk20] RFR: 8300195: Fall-through issue occurs when using record pattern in switch statements

[Jan Lahoda]

When converting pattern matching switches, cases with common prefix tests are factored out into separate sub-switches. But, when this happens, the cases generated are the statement cases, even if the original cases where rule cases. So, this may lead to an unintended fall through. The proposal here is to inject breaks with correct targets as needed.

Alternatively, we could keep the kind of the cases, but that is more tricky, as the cases must break the main switch, not the nested ones.

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Commit messages:
 - 8300195: Fall-through issue occurs when using record pattern in switch statements

Changes: https://git.openjdk.org/jdk20/pull/109/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk20&pr=109&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300195
  Stats: 124 lines in 2 files changed: 113 ins; 4 del; 7 mod
  Patch: https://git.openjdk.org/jdk20/pull/109.diff
  Fetch: git fetch https://git.openjdk.org/jdk20 pull/109/head:pull/109

PR: https://git.openjdk.org/jdk20/pull/109