8335589: Fix -Wzero-as-null-pointer-constant warnings in IdealLoopTree ctor

[kimbarrett]

Please review this trivial change to the IdealLoopTree constructor. The
initial values for some pointer-typed data members are changed from 0 to
nullptr. This removes ~275 -Wzero-as-null-pointer-constant when that warning
is enabled.

Testing: mach5 tier1

---

Progress

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

Issue

• JDK-8335589: Fix -Wzero-as-null-pointer-constant warnings in IdealLoopTree ctor (Enhancement - P4)

Reviewers

• Tobias Hartmann (@TobiHartmann - Reviewer)

Reviewing

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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:

8335589: Fix -Wzero-as-null-pointer-constant warnings in IdealLoopTree ctor

Reviewed-by: thartmann

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 7 new commits pushed to the master branch:

• 0db9bc5: 8335290: Rename ClassFile::transform to ClassFile::transformClass
• d51141e: 8321274: Rename ZipEntry.extraAttributes to ZipEntry.externalFileAttributes
• fac74b1: 8334229: Optimize InterpreterOopMap layout
• f9b4ea1: 8334220: Optimize Klass layout after JDK-8180450
• f7af450: 8335110: Fix instruction name and API spec inconsistencies in CodeBuilder
• 8a664a4: 8334734: Remove specialized readXxxEntry methods from ClassReader
• 3a2d426: 8334726: Remove accidentally exposed individual methods from Class-File API

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (24cd3f6e)

[TobiHartmann]

Looks good and trivial.

[kimbarrett]

Thanks for review, @TobiHartmann

[kimbarrett]

/integrate

[openjdk]

Going to push as commit 7bc8f9c.
Since your change was applied there have been 7 commits pushed to the master branch:

• 0db9bc5: 8335290: Rename ClassFile::transform to ClassFile::transformClass
• d51141e: 8321274: Rename ZipEntry.extraAttributes to ZipEntry.externalFileAttributes
• fac74b1: 8334229: Optimize InterpreterOopMap layout
• f9b4ea1: 8334220: Optimize Klass layout after JDK-8180450
• f7af450: 8335110: Fix instruction name and API spec inconsistencies in CodeBuilder
• 8a664a4: 8334734: Remove specialized readXxxEntry methods from ClassReader
• 3a2d426: 8334726: Remove accidentally exposed individual methods from Class-File API

Your commit was automatically rebased without conflicts.

[openjdk]

@kimbarrett Pushed as commit 7bc8f9c.

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