8265132: C2 compilation fails with assert "missing precedence edge"

[jamsheedcm]

Issue is similar to https://bugs.openjdk.java.net/browse/JDK-8261730
but happens at next https://github.com/jamsheedcm/jdk/blob/master/src/hotspot/share/opto/gcm.cpp#L830

Request for review

---

Progress

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Issue

• JDK-8265132: C2 compilation fails with assert "missing precedence edge"

Reviewing

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[bridgekeeper]

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[openjdk]

⚠️ @jamsheedcm This pull request contains merges that bring in commits not present in the target repository. Since this is not a "merge style" pull request, these changes will be squashed when this pull request in integrated. If this is your intention, then please ignore this message. If you want to preserve the commit structure, you must change the title of this pull request to Merge <project>:<branch> where <project> is the name of another project in the OpenJDK organization (for example Merge jdk:master).

[openjdk]

@jamsheedcm The following label will be automatically applied to this pull request:

• hotspot-compiler

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[mlbridge]

Webrevs

• 00: Full (5a857f86)

[jamsheedcm]

/label hotspot-compiler

[openjdk]

@jamsheedcm The hotspot-compiler label was already applied.

[jamsheedcm]

/label rfr

[openjdk]

@jamsheedcm The label rfr is not a valid label. These labels are valid:

• serviceability
• hotspot
• sound
• hotspot-compiler
• kulla
• i18n
• shenandoah
• jdk
• javadoc
• 2d
• security
• swing
• hotspot-runtime
• jmx
• build
• nio
• beans
• core-libs
• compiler
• net
• hotspot-gc
• hotspot-jfr
• awt