8373420: C2: Add true/false_proj*() methods for IfNode as a replacement for proj_out*(true/false)

[chhagedorn]

There are a lot of places in the code where we call proj_out*(true/false) on an IfNode. In some cases, we then cast the returned ProjNode back to IfProjNode or IfTrueNode/IfFalseNode. I often visit such code and now decided to clean this up.

The patch proposes new IfNode::true/false_proj*() methods that return IfTrueNode/IfFalseNode directly. I walked through all proj_out*() calls and replaced those that used a direct true/false or 1/0 as argument.

There are still more things to clean up in this area, for example, when we return ProjNode even though it should be an IfProjNode which requires more casting. But let's do that step by step in follow-up clean ups.

Thanks,
Christian

---

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Issue

• JDK-8373420: C2: Add true/false_proj*() methods for IfNode as a replacement for proj_out*(true/false) (Enhancement - P4)

Reviewers

• Damon Fenacci (@dafedafe - Committer)
• Roland Westrelin (@rwestrel - Reviewer)

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[openjdk]

@chhagedorn This change now passes all automated pre-integration checks.

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8373420: C2: Add true/false_proj*() methods for IfNode as a replacement for proj_out*(true/false)

Reviewed-by: dfenacci, roland

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At the time when this comment was updated there had been 23 new commits pushed to the master branch:

• a05d5d2: 8373579: Problem list compiler/runtime/Test7196199.java
• 180d8c1: 8372746: Some httpserver files could benefit from some formatting cleanup
• dc62552: 8371920: [TEST] Enable CMove tests on other platforms
• ... and 20 more: https://git.openjdk.org/jdk/compare/655e9cda3f6b1fa3a6f0553e7745aa088dde53e8...master

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@chhagedorn this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

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• 00: Full (7951e36d)

[dafedafe]

Nice cleanup. Thanks @chhagedorn. Looks good to me.

[chhagedorn]

Thanks Damon for your review!

[rwestrel]

Looks good to me.