8376400: C2: folding ifs may cause incorrect execution when trap is taken

[rwestrel]

This backport is not clean because of:

• unrelated context differences

• is_uncommon_trap_proj() has no default argument

The test case fails without the patch, passes with it. tier1 testing passes.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• JDK-8376400 needs maintainer approval
• Commit message must refer to an issue

Issue

• JDK-8376400: C2: folding ifs may cause incorrect execution when trap is taken (Bug - P3 - Requested)

Reviewers

• Christian Hagedorn (@chhagedorn - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back roland! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@rwestrel This change is no longer ready for integration - check the PR body for details.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[rwestrel]

/template append

[openjdk]

@rwestrel The pull request template has been appended to the pull request body

[mlbridge]

Webrevs

• 00: Full (f2d8786b)

[chhagedorn]

Looks good!

[openjdk]

⚠️ @rwestrel This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[GoeLin]

Hi @rwestrel
how urgent do you consider this?
Given this is a long standing issue, I would prefer to defer this to the next update, so that it
gets exposure in 27&25.