8303511: C2: assert(get_ctrl(n) == cle_out) during unrolling

[rwestrel]

In the same round of loop optimizations:

• PhaseIdealLoop::remix_address_expressions() creates a new AddP
  out of loop. It sets it control to
  n_loop->_head->in(LoopNode::EntryControl) which, because the loop is
  strip mined, is an OuterStripMinedLoop.

• The LoadI for that AddP is found to only have uses outside the
  loop and is cloned out of the loop. It's referenced by the outer
  loop's safepoint.

• The loop is unrolled. Unrolling follows the safepoint's inputs and
  find the new AddP with control set to the OuterStripMinedLoop
  and the assert fires.

No control should be set to an OuterStripMinedLoop. The fix is
straightforward and sets the control to the OuterStripMinedLoop
entry control.

---

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Issue

• JDK-8303511: C2: assert(get_ctrl(n) == cle_out) during unrolling

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer) ⚠️ Review applies to c2787438
• Tobias Hartmann (@TobiHartmann - Reviewer)

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[mlbridge]

Webrevs

• 01: Full - Incremental (f20e29b6)
• 00: Full (c2787438)

[vnkozlov]

Yes, this looks good.

[openjdk]

@rwestrel 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:

8303511: C2: assert(get_ctrl(n) == cle_out) during unrolling

Reviewed-by: kvn, thartmann

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 66 new commits pushed to the master branch:

• 97c25df: 8204550: NMT: RegionIterator does not need to keep _current_size
• 94eda53: 8201516: DebugNonSafepoints generates incorrect information
• c51d40c: 8303607: SunMSCAPI provider leaks memory and keys
• f64ed09: 8303540: Eliminate unnecessary reference to javac internal class
• ccfe167: 8298939: Refactor open/test/jdk/javax/rmi/ssl/SSLSocketParametersTest.sh to jtreg java test
• cfb0a25: 8303440: The "ZonedDateTime.parse" may not accept the "UTC+XX" zone id
• a97271e: 8301793: AlgorithmId should not encode a missing parameters field as NULL unless hardcoded
• cac81dd: 8303577: [JVMCI] OOME causes crash while translating exceptions
• 877ab65: 8303264: Refactor nsk/stress/strace to extract shared and remove redundant code
• ae8730f: 8303486: [REDO] Update ProcessTools.startProcess(...) to exit early if process exit before linePredicate is printed.
• ... and 56 more: https://git.openjdk.org/jdk/compare/99f5687eb192b249a4a4533578f56b131fb8f234...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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[TobiHartmann]

Looks good to me.

[rwestrel]

@vnkozlov @TobiHartmann thanks for the reviews!

[rwestrel]

/integrate

[openjdk]

Going to push as commit 3f2d929.
Since your change was applied there have been 67 commits pushed to the master branch:

• 7fbfc88: 8303534: Merge CompactibleSpace into ContiguousSpace
• 97c25df: 8204550: NMT: RegionIterator does not need to keep _current_size
• 94eda53: 8201516: DebugNonSafepoints generates incorrect information
• c51d40c: 8303607: SunMSCAPI provider leaks memory and keys
• f64ed09: 8303540: Eliminate unnecessary reference to javac internal class
• ccfe167: 8298939: Refactor open/test/jdk/javax/rmi/ssl/SSLSocketParametersTest.sh to jtreg java test
• cfb0a25: 8303440: The "ZonedDateTime.parse" may not accept the "UTC+XX" zone id
• a97271e: 8301793: AlgorithmId should not encode a missing parameters field as NULL unless hardcoded
• cac81dd: 8303577: [JVMCI] OOME causes crash while translating exceptions
• 877ab65: 8303264: Refactor nsk/stress/strace to extract shared and remove redundant code
• ... and 57 more: https://git.openjdk.org/jdk/compare/99f5687eb192b249a4a4533578f56b131fb8f234...master

Your commit was automatically rebased without conflicts.

[openjdk]

@rwestrel Pushed as commit 3f2d929.

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