8275416: G1: remove unnecessary make_referent_alive in precleaning phase

[albertnetymk]

Simple change of removing marking work in G1 precleaning. Evaluation using a contrived example shows ~20% reduction in precleaning.

Test: hotspot_gc

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Issue

• JDK-8275416: G1: remove unnecessary make_referent_alive in precleaning phase

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)
• Stefan Johansson (@kstefanj - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/6003/head:pull/6003
$ git checkout pull/6003

Update a local copy of the PR:
$ git checkout pull/6003
$ git pull https://git.openjdk.java.net/jdk pull/6003/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 6003

View PR using the GUI difftool:
$ git pr show -t 6003

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk/pull/6003.diff

[bridgekeeper]

👋 Welcome back ayang! 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]

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

• hotspot-gc

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[mlbridge]

Webrevs

• 00: Full (34212af1)

[openjdk]

@albertnetymk 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:

8275416: G1: remove unnecessary make_referent_alive in precleaning phase

Reviewed-by: tschatzl, sjohanss

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 95 new commits pushed to the master branch:

• dd622e5: 8275783: G1: fix incorrect region type documentation in HeapRegionType
• b2128a9: 8263155: Allow additional contents for DMG
• 1efe946: 8275712: Hashtable literal_size functions are broken
• fab3d6c: 8275761: Backout: JDK-8274794 Print all owned locks in hs_err file
• c978ca8: 8275344: -Xcheck:jni produces some warnings in the LCMS.c
• 6a466fe: 8202056: Expand serial warning to check for bad overloads of serial-related methods and ineffectual fields
• 4e9dd4b: 8275384: Change nested classes in jdk.jconsole to static nested classes
• 0961de4: 8275347: ciReplay: staticfield lines not properly terminated
• 7dd8237: 8275084: CDS warning when building with LOG=debug
• 49f9d80: 8243585: AlgorithmChecker::check throws confusing exception when it rejects the signer key
• ... and 85 more: https://git.openjdk.java.net/jdk/compare/d548f2fc0dbc9e7864dd1701873bbf3d12a75ecb...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.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[kstefanj]

Looks good.

I would love if the PR summary would contain a bit information. More or less just a copy of what's in the JBS description.

[albertnetymk]

Thanks for the review.

/integrate

[openjdk]

Going to push as commit 4e647aa.
Since your change was applied there have been 95 commits pushed to the master branch:

• dd622e5: 8275783: G1: fix incorrect region type documentation in HeapRegionType
• b2128a9: 8263155: Allow additional contents for DMG
• 1efe946: 8275712: Hashtable literal_size functions are broken
• fab3d6c: 8275761: Backout: JDK-8274794 Print all owned locks in hs_err file
• c978ca8: 8275344: -Xcheck:jni produces some warnings in the LCMS.c
• 6a466fe: 8202056: Expand serial warning to check for bad overloads of serial-related methods and ineffectual fields
• 4e9dd4b: 8275384: Change nested classes in jdk.jconsole to static nested classes
• 0961de4: 8275347: ciReplay: staticfield lines not properly terminated
• 7dd8237: 8275084: CDS warning when building with LOG=debug
• 49f9d80: 8243585: AlgorithmChecker::check throws confusing exception when it rejects the signer key
• ... and 85 more: https://git.openjdk.java.net/jdk/compare/d548f2fc0dbc9e7864dd1701873bbf3d12a75ecb...master

Your commit was automatically rebased without conflicts.

[openjdk]

@albertnetymk Pushed as commit 4e647aa.

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