[jdk18u] RFR: 8288303: C1: Miscompilation due to broken Class.getModifiers intrinsic

[Tobias Hartmann]

Backport of [JDK-8288303](https://bugs.openjdk.java.net/browse/JDK-8288303). Applies cleanly. Approval is pending.

Thanks,
Tobias

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Commit messages:
 - 8288303: C1: Miscompilation due to broken Class.getModifiers intrinsic

Changes: https://git.openjdk.org/jdk18u/pull/166/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk18u&pr=166&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8288303
  Stats: 141 lines in 2 files changed: 130 ins; 5 del; 6 mod
  Patch: https://git.openjdk.org/jdk18u/pull/166.diff
  Fetch: git fetch https://git.openjdk.org/jdk18u pull/166/head:pull/166

PR: https://git.openjdk.org/jdk18u/pull/166