[jdk17u] RFR: 8272570: C2: crash in PhaseCFG::global_code_motion

[Tobias Hartmann]

Backport of [JDK-8272570](https://bugs.openjdk.java.net/browse/JDK-8272570). Applies cleanly. Approval is pending.

Thanks,
Tobias

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Commit messages:
 - 8272570: C2: crash in PhaseCFG::global_code_motion

Changes: https://git.openjdk.java.net/jdk17u/pull/94/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=94&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8272570
  Stats: 55 lines in 2 files changed: 53 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/94.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/94/head:pull/94

PR: https://git.openjdk.java.net/jdk17u/pull/94