8331885: C2: meet between unloaded and speculative types is not symmetric

[iwanowww]

TypeInstPtr::xmeet_unloaded computes the MEET of two InstPtrs when at least one is unloaded, but doesn't preserve speculative part if one is present. It causes the corresponding assert to fail.

Proposed fix unconditionally keeps speculative part.

Testing: hs-tier1 - hs-tier4

---

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Issue

• JDK-8331885: C2: meet between unloaded and speculative types is not symmetric (Bug - P3)

Reviewers

• Roland Westrelin (@rwestrel - Reviewer) ⚠️ Review applies to fa5479f2
• Tobias Hartmann (@TobiHartmann - Reviewer) ⚠️ Review applies to fa5479f2

Reviewing

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👋 Welcome back vlivanov! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@iwanowww This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8331885: C2: meet between unloaded and speculative types is not symmetric

Reviewed-by: roland, thartmann

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At the time when this comment was updated there had been 37 new commits pushed to the master branch:

• d4c2edf: 8331855: Convert jdk.jdeps jdeprscan and jdeps to use the Classfile API
• beeffd4: 8332109: Convert remaining tests using com.sun.tools.classfile to ClassFile API
• e0d1c4b: 8321428: Deprecate for removal the package java.beans.beancontext
• 0b0445b: 8331724: Refactor j.l.constant implementation to internal package
• d84a8fd: 8332327: Return _methods_jmethod_ids field back in VMStructs
• f1ce9b0: 8331557: Serial: Refactor SerialHeap::do_collection
• 14198f5: 8329653: JLILaunchTest fails on AIX after JDK-8329131
• ae999ea: 8129418: JShell: better highlighting of errors in imports on demand
• 6422efa: 8332394: Add friendly output when @ir rule missing value
• 9160ef8: 8332237: [nmt] Remove the need for ThreadStackTracker::track_as_vm()
• ... and 27 more: https://git.openjdk.org/jdk/compare/8032d640c0d34fe507392a1d4faa4ff2005c771d...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

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[mlbridge]

Webrevs

• 01: Full - Incremental (0b873474)
• 00: Full (fa5479f2)

[rwestrel]

Looks good to me.

[TobiHartmann]

Looks good to me too. Please also run hs-comp-stress and hs-precheckin-comp testing.

[dcubed-ojdk]

@iwanowww - Will this fix be integrated soon? There are two solid failures in every
Tier5 job set and have been for quite a while.

[iwanowww]

Thanks for the reviews, Roland and Tobias.

hs-comp-stress and hs-precheckin-comp testing passed.

/integrate

[openjdk]

Going to push as commit 7652f98.
Since your change was applied there have been 47 commits pushed to the master branch:

• d6b7f9b: 8331851: Add specific regression leap year tests for Calendar.roll()
• b92bd67: 8332403: Anachronistic reference to Netscape Communicator in Swing API docs
• 8acdd2d: 8330565: C2: Multiple crashes with CTW after JDK-8316991
• 0a58cff: 8298405: Implement JEP 467: Markdown Documentation Comments
• 39a55e9: 8324809: compiler can crash with SOE while proving if two recursive types are disjoint
• b7ae0ae: 8328572: JFR: Use Class.forPrimitiveName(String)
• e611151: 8331281: RISC-V: C2: Support vector-scalar and vector-immediate bitwise logic instructions
• 44bdf99: 8332239: Improve CSS for block tags
• 9bb6169: 8317621: --add-script should support JavaScript modules
• 4eb1eaf: 8329617: Update stylesheet for specs and tool documentation
• ... and 37 more: https://git.openjdk.org/jdk/compare/8032d640c0d34fe507392a1d4faa4ff2005c771d...master

Your commit was automatically rebased without conflicts.

[openjdk]

@iwanowww Pushed as commit 7652f98.

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