RFR: JDK-8293978: Duplicate simple loop back-edge will crash the vm

[王超]

Duplicate back-edge of the following simple loop will make jvm crash.

<img width="458" alt="image" src="https://user-images.githubusercontent.com/25214855/190945327-ebce5342-bede-4fad-b940-088753034fa6.png">

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Commit messages:
 - Fix JDK-8293978

Changes: https://git.openjdk.org/jdk/pull/10329/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10329&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8293978
  Stats: 76 lines in 2 files changed: 75 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/10329.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10329/head:pull/10329

PR: https://git.openjdk.org/jdk/pull/10329