[jdk17u-dev] RFR: 8271056: C2: "assert(no_dead_loop) failed: dead loop detected" due to cmoving identity

[Goetz Lindenmaier]

I backport this for parity with 17.0.3-oracle.

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Commit messages:
 - Backport 54481394a3b7d36b2326e22e4aa910a3e8041b5c

Changes: https://git.openjdk.java.net/jdk17u-dev/pull/136/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u-dev&pr=136&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8271056
  Stats: 87 lines in 2 files changed: 85 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk17u-dev/pull/136.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u-dev pull/136/head:pull/136

PR: https://git.openjdk.java.net/jdk17u-dev/pull/136