8332548: GenShen: Factor generational mode out of gc helpers

[earthling-amzn]

Some of the generational mode support in shenandoahConcurrentGC.cpp and shenandoahDegeneratedGC.cpp can be factored into generational mode specific files and coalesced under fewer generational mode checks.

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed (1 review required, with at least 1 Committer)

Issue

• JDK-8332548: GenShen: Factor generational mode out of gc helpers (Task - P4)

Reviewers

• Y. Srinivas Ramakrishna (@ysramakrishna - Committer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/shenandoah.git pull/436/head:pull/436
$ git checkout pull/436

Update a local copy of the PR:
$ git checkout pull/436
$ git pull https://git.openjdk.org/shenandoah.git pull/436/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 436

View PR using the GUI difftool:
$ git pr show -t 436

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/shenandoah/pull/436.diff

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[bridgekeeper]

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[openjdk]

@earthling-amzn 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:

8332548: GenShen: Factor generational mode out of gc helpers

Reviewed-by: ysr

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 240 new commits pushed to the master branch:

• c4e2cf8: Merge
• 2f10a31: 8302850: Implement C1 clone intrinsic that reuses arraycopy code for primitive arrays
• c642f44: 8329839: Cleanup ZPhysicalMemoryBacking trace logging
• d04ac14: 8332236: javac crashes with module imports and implicitly declared class
• 4e77cf8: 8330795: C2: assert((uint)type <= T_CONFLICT && _zero_type[type] != nullptr) failed: bad type with -XX:-UseCompressedClassPointers
• 7b4ba7f: 8325932: Replace ATTRIBUTE_NORETURN with direct [[noreturn]]
• 0bb5ae6: 8332248: (fc) java/nio/channels/FileChannel/BlockDeviceSize.java failed with RuntimeException
• 4d32c60: 8322008: Exclude some CDS tests from running with -Xshare:off
• e91492a: 8313674: (fc) java/nio/channels/FileChannel/BlockDeviceSize.java should test for more block devices
• 95a6013: 8332042: Move MEMFLAGS to its own include file
• ... and 230 more: https://git.openjdk.org/shenandoah/compare/d77f426b0a7c8b2c7285ee43d978be2cf584a51f...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.

[mlbridge]

Webrevs

• 01: Full - Incremental (3c5cf2e1)
• 00: Full (31ffa8f6)

[ysramakrishna]

Changes look mostly good to me. Just some very minor comments and a check about brackets in diff in one place.

Approving it, since any changes there should not require my rereview.

[ysramakrishna]

LGTM; thanks for the changes!

[earthling-amzn]

/integrate

Thanks for the review!

[openjdk]

Going to push as commit 8f80827.
Since your change was applied there have been 240 commits pushed to the master branch:

• c4e2cf8: Merge
• 2f10a31: 8302850: Implement C1 clone intrinsic that reuses arraycopy code for primitive arrays
• c642f44: 8329839: Cleanup ZPhysicalMemoryBacking trace logging
• d04ac14: 8332236: javac crashes with module imports and implicitly declared class
• 4e77cf8: 8330795: C2: assert((uint)type <= T_CONFLICT && _zero_type[type] != nullptr) failed: bad type with -XX:-UseCompressedClassPointers
• 7b4ba7f: 8325932: Replace ATTRIBUTE_NORETURN with direct [[noreturn]]
• 0bb5ae6: 8332248: (fc) java/nio/channels/FileChannel/BlockDeviceSize.java failed with RuntimeException
• 4d32c60: 8322008: Exclude some CDS tests from running with -Xshare:off
• e91492a: 8313674: (fc) java/nio/channels/FileChannel/BlockDeviceSize.java should test for more block devices
• 95a6013: 8332042: Move MEMFLAGS to its own include file
• ... and 230 more: https://git.openjdk.org/shenandoah/compare/d77f426b0a7c8b2c7285ee43d978be2cf584a51f...master

Your commit was automatically rebased without conflicts.

[openjdk]

@earthling-amzn Pushed as commit 8f80827.

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