8387713: Shenandoah: Rework native card table barrier

[shipilev]

Follow-up for GenShen native card barrier, for the changes already delivered in 25.0.4.

Additional testing:

• Linux x86_64 server fastdebug, jcstress 8 hour run
• Linux x86_64 server fastdebug, hotspot_gc_shenandoah
• Linux AArch64 server fastdebug, hotspot_gc_shenandoah
• Linux x86_64 server fastdebug, hotspot_gc_shenandoah with -XX:TieredStopAtLevel=1
• Linux AArch64 server fastdebug, hotspot_gc_shenandoah with -XX:TieredStopAtLevel=1
• Linux x86_64 server fastdebug, all with -XX:+UseShenandoahGC -XX:ShenandoahGCMode=generational
• Linux AArch64 server fastdebug, all with -XX:+UseShenandoahGC -XX:ShenandoahGCMode=generational
• Linux x86_64 server fastdebug, all with -XX:+UseShenandoahGC -XX:TieredStopAtLevel=1 -XX:ShenandoahGCMode=generational
• Linux AArch64 server fastdebug, all with -XX:+UseShenandoahGC -XX:TieredStopAtLevel=1 -XX:ShenandoahGCMode=generational

---

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8387713 needs maintainer approval

Issue

• JDK-8387713: Shenandoah: Rework native card table barrier (Enhancement - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/749/head:pull/749
$ git checkout pull/749

Update a local copy of the PR:
$ git checkout pull/749
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/749/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 749

View PR using the GUI difftool:
$ git pr show -t 749

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/749.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

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[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @shipilev This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (90f87ae0)