Adjustment and new API for VarHandles

[fparain]

A few changes related to the work to fix the VarHandles code.
The keyword volatile is now a signal to prevent field flattening.
A new API in ValueClass allows Java code to query the atomicity characteristics of an array.

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Progress

• Change must not contain extraneous whitespace

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/valhalla.git pull/1401/head:pull/1401
$ git checkout pull/1401

Update a local copy of the PR:
$ git checkout pull/1401
$ git pull https://git.openjdk.org/valhalla.git pull/1401/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 1401

View PR using the GUI difftool:
$ git pr show -t 1401

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/valhalla/pull/1401.diff

[bridgekeeper]

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[openjdk]

@fparain 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:

Adjustment and new API for VarHandles

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

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[fparain]

/integrate

[openjdk]

Going to push as commit 6c73f22.

[openjdk]

@fparain Pushed as commit 6c73f22.

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

[mlbridge]

Webrevs

• 00: Full (c6e3d181)