8254780: EnterInterpOnlyModeClosure::completed() always returns true

[shipilev]

JDK-8238761 introduced this funky code:

class EnterInterpOnlyModeClosure : public HandshakeClosure {
 private:
  bool _completed;
 public:
  EnterInterpOnlyModeClosure() : HandshakeClosure("EnterInterpOnlyMode"), _completed(false) { }
  void do_thread(Thread* th) {
     ...
     _completed = true;
  }
  bool completed() {
    return _completed = true;
  }
};

It seems the flag is there to communicate that target thread indeed executed the handshake. But completed() sets the bool unconditionally and always returns true. And it is used in one and only place here:

     guarantee(hs.completed(), "Handshake failed: Target thread is not alive?");

...which means that guarantee always passes.

Attention @robehn :)

---

Progress

• Change must not contain extraneous whitespace
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Testing

	Linux x64	Windows x64	macOS x64
Build	✔️ (5/5 passed)	✔️ (2/2 passed)	✔️ (2/2 passed)
Test (tier1)	✔️ (9/9 passed)	✔️ (9/9 passed)	✔️ (9/9 passed)

Issue

• JDK-8254780: EnterInterpOnlyModeClosure::completed() always returns true

Reviewers

• Serguei Spitsyn (@sspitsyn - Reviewer)
• Robbin Ehn (@robehn - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/662/head:pull/662
$ git checkout pull/662

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (34ce2ce)

[sspitsyn]

It looks good.
Thank you for catching and fixing it!
Serguei

[openjdk]

@shipilev 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:

8254780: EnterInterpOnlyModeClosure::completed() always returns true

Reviewed-by: sspitsyn, rehn

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 12 new commits pushed to the master branch:

• 0c99b19: 8223347: Integration of Vector API (Incubator)
• 386e7e8: 8254789: ProblemList compiler/graalunit/HotspotTest.java
• cd33abb: 8249623: test @Ignore-d due to 7013634 should be returned back to execution
• b7daf84: 8254345: com/sun/jdi/JdwpAttachTest.java reports error incorrectly
• fde02e2: 8254012: NMT: MetaspaceSnapshot::snapshot uses wrong enum
• 96a1f08: 8254775: Microbenchmark StringIndexOfChar doesn't compile
• a6a3813: 8254761: Wrong intrinsic annotation used for StringLatin1.indexOfChar
• 738effa: 8254744: Clean-up CodeBlob::align_code_offset
• f71e8a6: 8173585: Intrinsify StringLatin1.indexOf(char)
• 95e68c6: 8254586: Replace fthrow() calls with simpler method calls in classFileParser.cpp
• ... and 2 more: https://git.openjdk.java.net/jdk/compare/dc262dfcbf89c6cbefda63fea00de7e795bfd883...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.

[robehn]

My bad, thanks @shipilev !

[shipilev]

/integrate

[openjdk]

@shipilev Since your change was applied there have been 12 commits pushed to the master branch:

• 0c99b19: 8223347: Integration of Vector API (Incubator)
• 386e7e8: 8254789: ProblemList compiler/graalunit/HotspotTest.java
• cd33abb: 8249623: test @Ignore-d due to 7013634 should be returned back to execution
• b7daf84: 8254345: com/sun/jdi/JdwpAttachTest.java reports error incorrectly
• fde02e2: 8254012: NMT: MetaspaceSnapshot::snapshot uses wrong enum
• 96a1f08: 8254775: Microbenchmark StringIndexOfChar doesn't compile
• a6a3813: 8254761: Wrong intrinsic annotation used for StringLatin1.indexOfChar
• 738effa: 8254744: Clean-up CodeBlob::align_code_offset
• f71e8a6: 8173585: Intrinsify StringLatin1.indexOf(char)
• 95e68c6: 8254586: Replace fthrow() calls with simpler method calls in classFileParser.cpp
• ... and 2 more: https://git.openjdk.java.net/jdk/compare/dc262dfcbf89c6cbefda63fea00de7e795bfd883...master

Your commit was automatically rebased without conflicts.

Pushed as commit da2f5ab.

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