8307625: Redundant receiver null check in LibraryCallKit::generate_method_call

[enothum]

The null_check_receiver() calls in generate_method_call are redundant as all callers of generate_method_call already perform this check. For future uses of generate_method_call a new assert is introduced that fails if the caller does not null check the receiver.
Also generally null_check_receiver() should be combined with stopped(), which was not the case here.

---

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Issue

• JDK-8307625: Redundant receiver null check in LibraryCallKit::generate_method_call (Enhancement - P4)

Reviewers

• Tobias Hartmann (@TobiHartmann - Reviewer) ⚠️ Review applies to 5763fde8
• Christian Hagedorn (@chhagedorn - Reviewer)

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• 02: Full - Incremental (47c05fd5)
• 01: Full - Incremental (5763fde8)
• 00: Full (a6292a6a)

[TobiHartmann]

Looks good to me.

[openjdk]

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

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

8307625: Redundant receiver null check in LibraryCallKit::generate_method_call

Reviewed-by: thartmann, chagedorn

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 124 new commits pushed to the master branch:

• 39c104d: 8310380: Handle problems in core-related tests on macOS when codesign tool does not work
• 526dba1: 8310130: C2: assert(false) failed: scalar_input is neither phi nor a matchin reduction
• 48e61c1: 8310728: Enable Zc:inline flag in Visual Studio build
• 56a73a6: 8309591: Socket.setOption(TCP_QUICKACK) uses wrong level
• afdaa2a: 8309109: AArch64: [TESTBUG] compiler/intrinsics/sha/cli/TestUseSHA3IntrinsicsOptionOnSupportedCPU.java fails on Neoverse N2 and V1
• 7f09435: 8310982: jdk/internal/util/ArchTest.java fails after JDK-8308452 failed with Method isARM()
• f07e396: 8310914: Remove 2 malformed java/foreign ProblemList entries
• a97f98f: 8310585: GetThreadState spec mentions undefined JVMTI_THREAD_STATE_MONITOR_WAITING
• 2cf5c2f: 8310238: [test bug] javax/swing/JTableHeader/6889007/bug6889007.java fails
• 269852b: 8294316: SA core file support is broken on macosx-x64 starting with macOS 12.x
• ... and 114 more: https://git.openjdk.org/jdk/compare/b896e3e02a28dde5d718cbc40f43a08f179269dd...master

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[chhagedorn]

Thanks for adding the null check as discussed offline together with @TobiHartmann. Looks good!

[TobiHartmann]

Just FTR: The intrinsified Unsafe::allocateUninitializedArray0 can currently not be called with a null receiver because it's private and only ever called from Unsafe::allocateUninitializedArray which would throw a NPE. But to be on the safe side in case this ever changes, we should emit a null check.

[enothum]

Thanks for the clarifications and reviews!

[enothum]

/integrate

[openjdk]

@enothum
Your change (at version 47c05fd) is now ready to be sponsored by a Committer.

[TobiHartmann]

/sponsor

[openjdk]

Going to push as commit c3f10e8.
Since your change was applied there have been 124 commits pushed to the master branch:

• 39c104d: 8310380: Handle problems in core-related tests on macOS when codesign tool does not work
• 526dba1: 8310130: C2: assert(false) failed: scalar_input is neither phi nor a matchin reduction
• 48e61c1: 8310728: Enable Zc:inline flag in Visual Studio build
• 56a73a6: 8309591: Socket.setOption(TCP_QUICKACK) uses wrong level
• afdaa2a: 8309109: AArch64: [TESTBUG] compiler/intrinsics/sha/cli/TestUseSHA3IntrinsicsOptionOnSupportedCPU.java fails on Neoverse N2 and V1
• 7f09435: 8310982: jdk/internal/util/ArchTest.java fails after JDK-8308452 failed with Method isARM()
• f07e396: 8310914: Remove 2 malformed java/foreign ProblemList entries
• a97f98f: 8310585: GetThreadState spec mentions undefined JVMTI_THREAD_STATE_MONITOR_WAITING
• 2cf5c2f: 8310238: [test bug] javax/swing/JTableHeader/6889007/bug6889007.java fails
• 269852b: 8294316: SA core file support is broken on macosx-x64 starting with macOS 12.x
• ... and 114 more: https://git.openjdk.org/jdk/compare/b896e3e02a28dde5d718cbc40f43a08f179269dd...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TobiHartmann @enothum Pushed as commit c3f10e8.

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