[jdk21u-dev] RFR: 8333366: C2: CmpU3Nodes are not pushed back to worklist in PhaseCCP leading to non-fixpoint assertion failure

[Martin Doerr]

Clean backport of [JDK-8333366](https://bugs.openjdk.org/browse/JDK-8333366).

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Commit messages:
 - Backport 7c83d7ab53f1f761a88a1d248b9a2f14980ef702

Changes: https://git.openjdk.org/jdk21u-dev/pull/705/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=705&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8333366
  Stats: 53 lines in 2 files changed: 51 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/705.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/705/head:pull/705

PR: https://git.openjdk.org/jdk21u-dev/pull/705