8287661: Fix and improve BitMap::print_on(outputStream*)

[shipilev]

Found these inconvenient during debugging using the BitMap::print_on. We pass the outputStream* to the method, but do not use it. Also, the output is hard to read for large bitmaps.

Sample output generated by gtest:

[0.292s][info][test] Bitmap (0 bits):
[0.292s][info][test] Bitmap (128 bits):
[0.292s][info][test]     0: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]    64: S....... ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test] Bitmap (1024 bits):
[0.292s][info][test]     0: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]    64: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   128: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   192: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   256: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   320: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   384: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   448: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   512: S....... ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   576: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   640: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   704: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   768: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   832: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   896: ........ ........ ........ ........ ........ ........ ........ ........
[0.292s][info][test]   960: ........ ........ ........ ........ ........ ........ ........ ........

It becomes clearer that bits 64 and 512 are set, respectively.

Additional testing:

• Linux x86_64 fastdebug, new gtest
• Linux x86_64 release, new gtest

---

Progress

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Issue

• JDK-8287661: Fix and improve BitMap::print_on(outputStream*)

Reviewers

• Stefan Karlsson (@stefank - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (921f646a)
• 00: Full (a9aaf61f)

[stefank]

Great that you found this!

[stefank]

Looks great! If we later change our mind about base 10 vs 2, we can revisit this.

[openjdk]

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

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8287661: Fix and improve BitMap::print_on(outputStream*)

Reviewed-by: stefank

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At the time when this comment was updated there had been 2 new commits pushed to the master branch:

• 67ecd30: 8287398: Allow concurrent execution of hotspot docker tests
• 8071b23: 8287237: (fs) Files.probeContentType returns null if filename contains hash mark on Linux

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[shipilev]

Any other opinions? I'll integrate it otherwise.

[shipilev]

/integrate

[openjdk]

Going to push as commit 625821d.
Since your change was applied there have been 34 commits pushed to the master branch:

• b544b8b: 8276789: Support C++ lambda in ResourceHashtable::iterate
• ba9ee8c: 8287748: Fix issues in java.lang.foreign package javadoc
• deb0653: 8287337: SnippetUtils should throw exceptions if snippets not found
• cbaeb00: 8287600: AA Ovals not rendered under metal
• 2776ff3: 8276266: Clean up incorrect client-libs ProblemList.txt entries
• 409157d: 8287125: [macos] Multiple jpackage tests fail/timeout on same host
• b5a646e: 8287425: Remove unnecessary register push for MacroAssembler::check_klass_subtype_slow_path
• 26048ea: 8287695: Use String.contains() instead of String.indexOf() in jdk.hotspot.agent
• 37e1835: 8287746: ProblemList jni/nullCaller/NullCallerTest.java
• 26d2426: 8287340: Refactor old code using StringTokenizer in locale related code
• ... and 24 more: https://git.openjdk.java.net/jdk/compare/774928f9447e961ec26a76e03dbf2143ffdcc05d...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev Pushed as commit 625821d.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[DamonFool]

Any other opinions? I'll integrate it otherwise.

There seems to be a regression: #9029 .
Please have a look.
Thanks.