8247299: [lworld] Disable UseBiasedLocking by default

[MrSimms]

Disabled UseBiasedLocking, and reorganized markWord to serve Valhalla requirements (see also JDK-8247298 for motivation).

Actual UseBiasedLocking code remains simply to avoid future conflicts. Since static constants have changed and UseBiasedLocking is deprecated, Valhalla assumes it will be removed, and it is not only disabled "by default", but now unusable.

Tier1-3 testing clean

---

Progress

• Change must not contain extraneous whitespace

Testing

	Linux x64	Windows x64	macOS x64
Build	❌ (2/5 failed)	❌ (2/2 failed)	✔️ (2/2 passed)
Test (tier1)			❌ (1/9 failed)

Failed test tasks

• Linux x64 (build hotspot minimal)
• Linux x64 (build hotspot zero)
• Windows x64 (build debug)
• Windows x64 (build release)
• macOS x64 (langtools/tier1)

Issue

• JDK-8247299: [lworld] Disable UseBiasedLocking by default

Reviewers

• Frederic Parain (@fparain - Committer)

Download

$ git fetch https://git.openjdk.java.net/valhalla pull/234/head:pull/234
$ git checkout pull/234

[bridgekeeper]

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

[openjdk]

@MrSimms 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:

8247299: [lworld] Disable UseBiasedLocking by default

Reviewed-by: fparain

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 1 new commit pushed to the lworld branch:

• 28b90dc: 8255054: Fix test broken by incorrect removal of java.lang.ValueBased

Please see this link for an up-to-date comparison between the source branch of this pull request and the lworld branch.
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

• 00: Full (4b02f03)

[MrSimms]

/issue JDK-8247299

[openjdk]

@MrSimms This issue is referenced in the PR title - it will now be updated.

[fparain]

Looks good to me.

Fred

[MrSimms]

/integrate

[openjdk]

@MrSimms Since your change was applied there have been 2 commits pushed to the lworld branch:

• 3167856: 8254797: [Development] Define & apply annotation jdk.internal.ValueBased
• 28b90dc: 8255054: Fix test broken by incorrect removal of java.lang.ValueBased

Your commit was automatically rebased without conflicts.

Pushed as commit 3a7c9fe.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[kuksenko]

Comment. It won't work for arrays properly.
file: oop.inline.hpp line 207

• bool oopDesc::is_flatArray() const { return klass()->is_flatArray_klass(); }

• bool oopDesc::is_flatArray() const { return mark().is_flat_array(); }

Array maybe locked. So is_flatArray should be like this:
bool oopDesc::is_flatArray() const {
if(mark().is_unlocked()) {
return mark().is_flat_array();
} else {
return klass()->is_flatArray_klass();
}
}