8358735: GenShen: block_start() may be incorrect after class unloading

[rgithubli]

Backport of JDK-8358735 and its two follow up fixes: JDK-8372110 and JDK-8371854.

The backport of the original issue (JDK-8358735) is almost clean except that atomic.hpp was renamed to atomicAccess.hpp in the later versions, and I had to resolve the conflict by retaining atomic.hpp import.

The two follow up backports are clean.

Our internal application crashed and we identified JDK-8358735 was the root cause. Backporting it for the fix.

Testing: all GHA tests passed.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8358735 needs maintainer approval

Issue

• JDK-8358735: GenShen: block_start() may be incorrect after class unloading (Bug - P3)

Reviewers

• Kelvin Nilsen (@kdnilsen - no project role)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/19/head:pull/19
$ git checkout pull/19

Update a local copy of the PR:
$ git checkout pull/19
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/19/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 19

View PR using the GUI difftool:
$ git pr show -t 19

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/19.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]

⚠️ @rgithubli 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

• 01: Full - Incremental (0fbe598e)
• 00: Full (ca08e4d2)