[jdk21u-dev] RFR: 8319372: C2 compilation fails with "Bad immediate dominator info"

[Aleksey Shipilev]

Clean backport to fix C2 bug and better parity.

Testing:
 - [x] New regression tests fail with the fix and pass with it
 - [ ] Linux x86_64 server fastdebug, `tier{1,2,3,4}`
 - [ ] Linux x86_64 server fastdebug, `tier{1,2,3,4}`

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Commit messages:
 - Backport 7766785098816cfcdae3479540cdc866c1ed18ad

Changes: https://git.openjdk.org/jdk21u-dev/pull/157/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=157&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319372
  Stats: 244 lines in 4 files changed: 171 ins; 73 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/157.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/157/head:pull/157

PR: https://git.openjdk.org/jdk21u-dev/pull/157