8318051: Duration.between uses exceptions for control flow

[eamonnmcmanus]

The existing logic uses nanosecond arithmetic to compute Duration.between. Since that can overflow for durations greater than 292 years, it has a try/catch that falls back to computing the seconds part and adjusting that for nanoseconds. However, exception handling is typically very expensive, so in cases like the one in the linked bug this method was a performance trap.

The new logic is essentially the old catch block. It needs a special case for when the number of seconds is 0, so it is slightly slower in that case. But in other cases it is probably somewhat faster, because it avoids a division and associated mod.

The test coverage in TCKDuration is already very thorough so no new tests are needed.

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Issue

• JDK-8318051: Duration.between uses exceptions for control flow (Bug - P4)

Reviewers

• Roger Riggs (@RogerRiggs - Reviewer)

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[RogerRiggs]

Did you identify an existing test that reproduces your initial issue case?
Duration.between(instant, Instant.MAX).compareTo(duration) < 0

Otherwise, looks good

[eamonnmcmanus]

Yes, what I tried was just removing the catch-block from the existing code and verifying that TCKDuration fails with ArithmeticException. It calls between on LocalDateTime values that are 800 years apart, which is enough to trigger nanosecond overflow. So both the original try and the original catch are tested.

[RogerRiggs]

Thanks for the fix and confirming the test.

[openjdk]

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

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After integration, the commit message for the final commit will be:

8318051: Duration.between uses exceptions for control flow

Reviewed-by: rriggs

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At the time when this comment was updated there had been 27 new commits pushed to the master branch:

• 1165037: 8318569: Add getter methods for Locale and Patterns in ListFormat
• 6f35274: 8318702: G1: Fix nonstandard indentation in g1HeapTransition.cpp
• e272098: 8318160: javac does not reject private method reference with type-variable receiver
• 54c613a: 8318693: Fix rendering for code blocks nested under list items in building.md
• e67550c: 8318509: x86 count_positives intrinsic broken for -XX:AVX3Threshold=0
• 8879c78: 8317689: [JVMCI] include error message when CreateJavaVM in libgraal fails
• f9795d0: 8318222: RISC-V: C2 CmpU3
• d1077d6: 8316046: x64 platforms unecessarily save xmm16-31 when UseAVX >= 3
• 21d8a47: 8318701: Fix copyright year
• d4b7612: 8318240: [AIX] Cleaners.java test failure
• ... and 17 more: https://git.openjdk.org/jdk/compare/8d9a4b43f4fff30fd217dab2c224e641cb913c18...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.

[eamonnmcmanus]

/integrate

[openjdk]

Going to push as commit 9c819fd.
Since your change was applied there have been 29 commits pushed to the master branch:

• 1ddf826: 8316964: Security tools should not call System.exit
• 1f2a80b: 8318306: java/util/Arrays/Sorting.java fails with "Array is not sorted at 8228-th position: 8251.0 and 8153.0"
• 1165037: 8318569: Add getter methods for Locale and Patterns in ListFormat
• 6f35274: 8318702: G1: Fix nonstandard indentation in g1HeapTransition.cpp
• e272098: 8318160: javac does not reject private method reference with type-variable receiver
• 54c613a: 8318693: Fix rendering for code blocks nested under list items in building.md
• e67550c: 8318509: x86 count_positives intrinsic broken for -XX:AVX3Threshold=0
• 8879c78: 8317689: [JVMCI] include error message when CreateJavaVM in libgraal fails
• f9795d0: 8318222: RISC-V: C2 CmpU3
• d1077d6: 8316046: x64 platforms unecessarily save xmm16-31 when UseAVX >= 3
• ... and 19 more: https://git.openjdk.org/jdk/compare/8d9a4b43f4fff30fd217dab2c224e641cb913c18...master

Your commit was automatically rebased without conflicts.

[openjdk]

@eamonnmcmanus Pushed as commit 9c819fd.

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