8316181: Move the fast locking implementation out of the .ad files

[stefank]

Some platforms put the fast locking implementation in the C2_MacroAssembler class, while others have it in the .ad files. I'd like to propose that we unify this a bit and move the code out of the .ad files.

The benefit is consistency between the platforms but also that it is easier to work with the C++ code when it is in plain C++ files and not in the .ad files.

The implementation is a pure copy of the code except that the section:

    C2_MacroAssembler _masm(&cbuf);
    Register oop = as_Register($object$$reg);
    Register box = as_Register($box$$reg);
    Register disp_hdr = as_Register($tmp$$reg);
    Register tmp = as_Register($tmp2$$reg);

has been replaced with:

  Register oop = objectReg;
  Register box = boxReg;
  Register disp_hdr = tmpReg;
  Register tmp = tmp2Reg;

and the references to __ have been removed.

This change affects AArch64 and RISC-V

Tested with tier1-3 on AArch64

This PR depends on #15709

---

Progress

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• Commit message must refer to an issue

Issue

• JDK-8316181: Move the fast locking implementation out of the .ad files (Enhancement - P4)

Reviewers

• Tobias Hartmann (@TobiHartmann - Reviewer) ⚠️ Review applies to 0efabfe1
• Roman Kennke (@rkennke - Reviewer)
• Fei Yang (@RealFYang - Reviewer)

Reviewing

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Update a local copy of the PR:
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[bridgekeeper]

👋 Welcome back stefank! A progress list of the required criteria for merging this PR into pr/15709 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

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

• hotspot-compiler

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[mlbridge]

Webrevs

• 02: Full - Incremental (00fa4e18)
• 01: Full - Incremental (0efabfe1)
• 00: Full (0efabfe1)

[TobiHartmann]

Looks good to me.

[openjdk-notifier]

The parent pull request that this pull request depends on has now been integrated and the target branch of this pull request has been updated. This means that changes from the dependent pull request can start to show up as belonging to this pull request, which may be confusing for reviewers. To remedy this situation, simply merge the latest changes from the new target branch into this pull request by running commands similar to these in the local repository for your personal fork:

git checkout fast_locking_unification
git fetch https://git.openjdk.org/jdk.git master
git merge FETCH_HEAD
# if there are conflicts, follow the instructions given by git merge
git commit -m "Merge master"
git push

[openjdk]

@stefank 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:

8316181: Move the fast locking implementation out of the .ad files

Reviewed-by: thartmann, rkennke, fyang

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 master branch:

• 14408bc: 8315973: Remove unused fields from ThreadLocalRandom

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[rkennke]

Looks good, thank you!

[RealFYang]

LGTM. I have tested both #15709 and this one on linux-riscv64 platform. Result is clean.

[stefank]

Thanks @rkennke and @RealFYang for the reviews!
/integrate

[openjdk]

Going to push as commit b48dbf6.
Since your change was applied there have been 3 commits pushed to the master branch:

• 8f4dfc4: 8316164: Opensource JMenuBar manual test
• 33c62e4: 8316154: Opensource JTextArea manual tests
• 14408bc: 8315973: Remove unused fields from ThreadLocalRandom

Your commit was automatically rebased without conflicts.

[openjdk]

@stefank Pushed as commit b48dbf6.

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