8387721: C2: Print Node barrier data

[shipilev]

Improves diagnostics with Late Barrier Expansion GCs (ZGC and G1 in JDK 25u).

There are minor conflicts, due to MemNode::dump_adr_type signature difference which accepts const Node* mem as the argument in JDK 25u.

Additional testing:

• Linux x86_64 server fastdebug, hotspot_compiler

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• JDK-8387721 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8387721: C2: Print Node barrier data (Enhancement - P4 - Requested)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/718/head:pull/718
$ git checkout pull/718

Update a local copy of the PR:
$ git checkout pull/718
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/718/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 718

View PR using the GUI difftool:
$ git pr show -t 718

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/718.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.

[mlbridge]

Webrevs

• 00: Full (521b4a85)

[phohensee]

25u's dump_adr_type doesn't use it's mem argument: I guess that got cleaned up somewhere else.

[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.

[shipilev]

/approval request Improves compiler-side diagnostics with Late Barrier Expansion GCs (ZGC and G1 in JDK 25u). Small patch, but requires minor adaptations. Testing passes. Risk is on lower side: compiler diagnostic code, non-product code, no customer exposure.

[openjdk]

@shipilev
8387721: The approval request has been created successfully.