8288933: Improve the implementation of Double/Float.isInfinite

[merykitty]

Improve the implementation of Double/Float.isInfinite to reduce branching. Using > comparison with MAX_VALUE instead of == with POSITIVE_INFINITY improves code emission on x86 and produces similar code for arm. This is also the way gcc implements std::isinf on x86 and arm (clang uses the pattern Math.abs(v) == POSITIVE_INFINITY on arm).

test/micro/org/openjdk/bench/java/lang/FPComparison.java has been added in #8525, the results are reshown here:

Benchmark                      Mode  Cnt     Score     Error    Score     Error   Unit   Ratio
FPComparison.isInfiniteDouble  avgt    5  1232.800 ±  31.677  621.185 ±  11.935  ns/op    1.98
FPComparison.isInfiniteFloat   avgt    5  1234.708 ±  70.239  623.566 ±  15.206  ns/op    1.98

Thank you very much.

---

Progress

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Issue

• JDK-8288933: Improve the implementation of Double/Float.isInfinite

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[bridgekeeper[bot]]

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[mlbridge[bot]]

Webrevs

• 00: Full (ece55f40)

[jddarcy]

@merykitty, the proposed change is functionally correct.

@cl4es, what set of platforms do we usually consider for evaluating performance changes like this?

[cl4es]

@cl4es, what set of platforms do we usually consider for evaluating performance changes like

A mix of x86 and aarch64 systems, some old, some new. We could run the microbenchmark on our internal performance system to verify the reported performance gain. I assume the first score column is the baseline and the second the patched version, so a 2x gain on x86, right @merykitty?

[merykitty]

@cl4es yes the former numbers are the baseline and the latters are of this patch

[bridgekeeper[bot]]

@merykitty This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[merykitty]

May I have a review for this patch, please? Thanks a lot.

[openjdk[bot]]

@merykitty 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:

8288933: Improve the implementation of Double/Float.isInfinite

Reviewed-by: redestad, darcy

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 964 new commits pushed to the master branch:

• 00befddd7ce97d324250807824469daaa9434eef: 8292675: Add identity transformation for removing redundant AndV/OrV nodes
• 7169ee5c73c130aacce73cbd3f88377ec07c8311: 8293477: IGV: Upgrade to Netbeans Platform 15
• 3dd94f33b2dddf8ea28805499d110c2347476c19: 8292671: Hotspot Style Guide should allow covariant returns
• 9d6b0285f53599816c30393b87d16772ef6314b7: 8234315: GTK LAF does not gray out disabled JMenu
• 812d805a488597cb9ab6b375869bc6748fd7fa94: 6447816: Provider filtering (getProviders) is not working with OR'd conditions
• 43e191d64b0094cc1ece61929c32e017ee90c0c8: 8293524: RISC-V: Use macro-assembler functions as appropriate
• 14eb5ad0dc987ffe3621f4eeeebeb6b5a2cd691b: 8291753: Add JFR event for GC CPU Time
• 30d4145e2edd2d3e4cbaa8b01f7639ab53bc0991: 8293230: x86_64: Move AES and GHASH stub definitions into separate source files
• 4c5501c31c7ab8fa7d1a6ce479060a899514c671: 8293548: ProblemList sun/management/jmxremote/bootstrap/RmiBootstrapTest.java#id1 on linux-x64
• 46e6e41b9a35c8665eb31be2f8c36bbdcc90564a: 8293051: Further refactor javac after removal of -source/-target/--release 7
• ... and 954 more: https://git.openjdk.org/jdk/compare/2bf5c9a6877b51377a535c6021a9e38549c89029...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.

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➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[merykitty]

@cl4es Thanks very much for your review, I believe this change is trivial, right? /integrate

[openjdk[bot]]

@merykitty Your change (at version ece55f40c0db9b5974643c2b702257ed0f22112b) is now ready to be sponsored by a Committer.

[jddarcy]

/sponsor

[openjdk[bot]]

Going to push as commit a14c3a493a98792a61de253920bb177a5c35fd8e. Since your change was applied there have been 964 commits pushed to the master branch:

• 00befddd7ce97d324250807824469daaa9434eef: 8292675: Add identity transformation for removing redundant AndV/OrV nodes
• 7169ee5c73c130aacce73cbd3f88377ec07c8311: 8293477: IGV: Upgrade to Netbeans Platform 15
• 3dd94f33b2dddf8ea28805499d110c2347476c19: 8292671: Hotspot Style Guide should allow covariant returns
• 9d6b0285f53599816c30393b87d16772ef6314b7: 8234315: GTK LAF does not gray out disabled JMenu
• 812d805a488597cb9ab6b375869bc6748fd7fa94: 6447816: Provider filtering (getProviders) is not working with OR'd conditions
• 43e191d64b0094cc1ece61929c32e017ee90c0c8: 8293524: RISC-V: Use macro-assembler functions as appropriate
• 14eb5ad0dc987ffe3621f4eeeebeb6b5a2cd691b: 8291753: Add JFR event for GC CPU Time
• 30d4145e2edd2d3e4cbaa8b01f7639ab53bc0991: 8293230: x86_64: Move AES and GHASH stub definitions into separate source files
• 4c5501c31c7ab8fa7d1a6ce479060a899514c671: 8293548: ProblemList sun/management/jmxremote/bootstrap/RmiBootstrapTest.java#id1 on linux-x64
• 46e6e41b9a35c8665eb31be2f8c36bbdcc90564a: 8293051: Further refactor javac after removal of -source/-target/--release 7
• ... and 954 more: https://git.openjdk.org/jdk/compare/2bf5c9a6877b51377a535c6021a9e38549c89029...master

Your commit was automatically rebased without conflicts.

[openjdk[bot]]

@jddarcy @merykitty Pushed as commit a14c3a493a98792a61de253920bb177a5c35fd8e.

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