8337782: Use THROW_NULL instead of THROW_0 in pointer contexts in prims code

[kimbarrett]

Please review this trivial change that, in places in prims code where a
pointer value is required, replaces uses of THROW_0 and THROW_MSG_0 with
THROW_NULL and THROW_MSG_NULL respectively.

Testing: mach5 tier1

---

Progress

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• Commit message must refer to an issue

Issue

• JDK-8337782: Use THROW_NULL instead of THROW_0 in pointer contexts in prims code (Enhancement - P4)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)
• David Holmes (@dholmes-ora - Reviewer)

Reviewing

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$ git checkout pull/20456

Update a local copy of the PR:
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$ git pull https://git.openjdk.org/jdk.git pull/20456/head

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$ git pr checkout 20456

View PR using the GUI difftool:
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https://git.openjdk.org/jdk/pull/20456.diff

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[bridgekeeper]

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

[openjdk]

@kimbarrett 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:

8337782: Use THROW_NULL instead of THROW_0 in pointer contexts in prims code

Reviewed-by: shade, dholmes

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 20 new commits pushed to the master branch:

• 73718fb: 8337788: RISC-V: Cleanup code in MacroAssembler::reserved_stack_check
• 965d6b9: 8335836: serviceability/jvmti/StartPhase/AllowedFunctions/AllowedFunctions.java fails with unexpected exit code: 112
• 7146dae: 8337783: Use THROW_NULL instead of THROW_0 in pointer contexts in misc runtime code
• 431d4f7: 8337785: Fix simple -Wzero-as-null-pointer-constant warnings in x86 code
• e2c07d5: 8337299: vmTestbase/nsk/jdb/stop_at/stop_at002/stop_at002.java failure goes undetected
• 08f697f: 8337819: Update GHA JDKs to 22.0.2
• 42652b2: 8337787: Fix -Wzero-as-null-pointer-constant warnings when JVMTI feature is disabled
• 807186f: 8337784: Fix simple -Wzero-as-null-pointer-constant warnings in linux/posix code
• e68df52: 8337054: JDK 23 RDP2 L10n resource files update
• 9856216: 8336928: GHA: Bundle artifacts removal broken
• ... and 10 more: https://git.openjdk.org/jdk/compare/367e0a65561f95aad61b40930d5f46843fee3444...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.

[openjdk]

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[mlbridge]

Webrevs

• 00: Full (33c9f374)

[shipilev]

Current changes look okay. I have not checked these caught all the instances of THROW_MSG_0 in those files, did you check that somehow?

[kimbarrett]

Current changes look okay. I have not checked these caught all the instances of THROW_MSG_0 in those files, did you check that somehow?

I'm developing these changes on a branch that has -Wzero-as-null-pointer-constant enabled, then cherry picking
related groups of changes into a separate branch for a PR. I look at the build logs from the first to find a given set of
warnings. So there may be more warnings coming from some of those files, but not from that specific usage. Although
this means I might touch some files more than once, it has seemed to me better to keep most PRs simple and easy to
review.

[dholmes-ora]

Okay. Thanks for cleaning up.

[kimbarrett]

Thanks for reviews @shipilev and @dholmes-ora

[kimbarrett]

/integrate

[openjdk]

Going to push as commit 2057594.
Since your change was applied there have been 20 commits pushed to the master branch:

• 73718fb: 8337788: RISC-V: Cleanup code in MacroAssembler::reserved_stack_check
• 965d6b9: 8335836: serviceability/jvmti/StartPhase/AllowedFunctions/AllowedFunctions.java fails with unexpected exit code: 112
• 7146dae: 8337783: Use THROW_NULL instead of THROW_0 in pointer contexts in misc runtime code
• 431d4f7: 8337785: Fix simple -Wzero-as-null-pointer-constant warnings in x86 code
• e2c07d5: 8337299: vmTestbase/nsk/jdb/stop_at/stop_at002/stop_at002.java failure goes undetected
• 08f697f: 8337819: Update GHA JDKs to 22.0.2
• 42652b2: 8337787: Fix -Wzero-as-null-pointer-constant warnings when JVMTI feature is disabled
• 807186f: 8337784: Fix simple -Wzero-as-null-pointer-constant warnings in linux/posix code
• e68df52: 8337054: JDK 23 RDP2 L10n resource files update
• 9856216: 8336928: GHA: Bundle artifacts removal broken
• ... and 10 more: https://git.openjdk.org/jdk/compare/367e0a65561f95aad61b40930d5f46843fee3444...master

Your commit was automatically rebased without conflicts.

[openjdk]

@kimbarrett Pushed as commit 2057594.

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