8371874: AOTLinkedClassBulkLoader::preload_classes() should not allocate heap objects

[iklam]

AOTLinkedClassBulkLoader::preload_classes() indirectly calls java_lang_Class::restore_archived_mirror() which can allocate an int array for the init_lock. However, the init_lock has already been allocated during AOT cache assembly :

java_lang_Class::create_scratch_mirror()
-> allocate_mirror()
  -> initialize_mirror_fields()
    -> set_init_lock()

So there's no need to allocate it again in the production run.

---

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Issue

• JDK-8371874: AOTLinkedClassBulkLoader::preload_classes() should not allocate heap objects (Bug - P3)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)
• Albert Mingkun Yang (@albertnetymk - Reviewer)

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[openjdk]

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

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8371874: AOTLinkedClassBulkLoader::preload_classes() should not allocate heap objects

Reviewed-by: shade, ayang

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At the time when this comment was updated there had been 56 new commits pushed to the master branch:

• 36daa26: 8371860: Make non-public methods in java_lang_Class private
• 5d65c23: 8370492: [Linux] Update cpu shares to cpu.weight mapping function
• 4cc655a: 8371791: G1: Improve accuracy of G1CollectedHeap::non_young_occupancy_after_allocation()
• ... and 53 more: https://git.openjdk.org/jdk/compare/76a1109d6fc7baac9ebc7accff800ef8927931bb...master

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[mlbridge]

Webrevs

• 00: Full (50340cb0)

[iklam]

Thanks @albertnetymk @shipilev for the review
/integrate

[openjdk]

Going to push as commit 58b601a.
Since your change was applied there have been 59 commits pushed to the master branch:

• 6e7eaf4: 8371591: VerifyJimage test incorrectly skips all tests when comparing directory structure
• 10f262a: 8371804: C2: Tighten up LoadNode::Value comments after JDK-8346184
• 466cb38: 8371885: Mark UseCompressedClassPointers as obsolete for JDK 27
• ... and 56 more: https://git.openjdk.org/jdk/compare/76a1109d6fc7baac9ebc7accff800ef8927931bb...master

Your commit was automatically rebased without conflicts.

[openjdk]

@iklam Pushed as commit 58b601a.

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