8303451: Synchronization entry in C2 debug info is misleading

[quadhier]

This should fix JDK-8303451.

It tries to correct some misleading code comments printed by -XX:+PrintAssembly.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
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• Commit message must refer to an issue

Issue

• JDK-8303451: Synchronization entry in C2 debug info is misleading (Enhancement - P4)

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[mlbridge]

Webrevs

• 02: Full - Incremental (af3c98be)
• 01: Full - Incremental (362fc750)
• 00: Full (2f21f37b)

[quadhier]

Hi @TobiHartmann , could you please review this change? Thanks in advance!

[TobiHartmann]

Couldn't we detect if the method is synchronized and adjust the comment accordingly?

[TobiHartmann]

@dean-long also had some suggestions in JDK-8201516 and might want to have a look.

[quadhier]

Hi, @TobiHartmann thanks for your advice. It seems that this PR should do more than a simple change of code comment. I will investigate it further.

[quadhier]

Thanks to your helpful discussions, the current change looks better but is still far from perfect.

I think UnwindBci is used in an exception-throwing case, but there seem to be no more appropriate bci used for the state "at method exit while not unlocked yet". I will continue looking into this.

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@quadhier This pull request has been inactive for more than 8 weeks and will now be automatically closed. If you would like to continue working on this pull request in the future, feel free to reopen it! This can be done using the /open pull request command.