[jdk21u] RFR: 8316746: Top of lock-stack does not match the unlocked object

Tue Nov 14 14:53:45 UTC 2023

Backport of PPC64 fix [JDK-8316746](https://bugs.openjdk.org/browse/JDK-8316746). The issue was observed with the new lightweight locking, but the bug is not limited to it. C2 OSR compiled methods may be wrong when the monitor slots were reused in opposite order (see included test).

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Commit messages:
 - Backport 7d8adfa855e51a90c2f125fc20a06f9a488e6248

Changes: https://git.openjdk.org/jdk21u/pull/361/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=361&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316746
  Stats: 160 lines in 7 files changed: 76 ins; 44 del; 40 mod
  Patch: https://git.openjdk.org/jdk21u/pull/361.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/361/head:pull/361

PR: https://git.openjdk.org/jdk21u/pull/361