[jdk21u-dev] RFR: 8325372: Shenandoah: SIGSEGV crash in unnecessary_acquire due to LoadStore split through phi

[Dan Lutker]

Backporting to 21 which also has the same issue.

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Commit messages:
 - Backport 5d414da50459b7a1e6f0f537ff3b318854b2c427

Changes: https://git.openjdk.org/jdk21u-dev/pull/306/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=306&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325372
  Stats: 100 lines in 4 files changed: 99 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/306.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/306/head:pull/306

PR: https://git.openjdk.org/jdk21u-dev/pull/306