8275908: Record null_check traps for calls and array_check traps in the interpreter

[simonis]

null_checks occurring at invoke bytecodes are currently not recorded by the profiler. This leads to unnecessary uncommon traps, deoptimizations and recompilations for exceptions which already occurred before the compilation (i.e. are "hot"). This change fixes the problem in the interpreter.

array_checks are currently recorded as class_checks in the interpreter and therefore not recognized by the compiler. This again leads to uncommon traps, deoptimizations and recompilations. This change unifies the handling of array_checks in the interpreter and compiler and prevents unnecessary recompilation.

The test is a stripped down version of a test which was developed for JDK-8273563: Improve performance of implicit exceptions with -XX:-OmitStackTraceInFastThrow (still under review). It introduces an extension to the Whitebox API to expose the decompile, deopt and trap counters which is also required for testing JDK-8273563. I think (and hope) it will also be helpful for others in the future.

---

Progress

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Issue

• JDK-8275908: Record null_check traps for calls and array_check traps in the interpreter

Reviewers

• Christian Hagedorn (@chhagedorn - Reviewer)
• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/6541/head:pull/6541
$ git checkout pull/6541

Update a local copy of the PR:
$ git checkout pull/6541
$ git pull https://git.openjdk.java.net/jdk pull/6541/head

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Checkout this PR locally:
$ git pr checkout 6541

View PR using the GUI difftool:
$ git pr show -t 6541

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https://git.openjdk.java.net/jdk/pull/6541.diff

[bridgekeeper]

👋 Welcome back simonis! 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]

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[mlbridge]

Webrevs

• 02: Full - Incremental (c8564d08)
• 01: Full - Incremental (58a107db)
• 00: Full (6d12c341)

[chhagedorn]

Otherwise, it looks good to me! But would be good to get a second review for it.

Nice test!

[TheRealMDoerr]

Nice change! Looks good to me besides what was already said.

[simonis]

@TheRealMDoerr, @chhagedorn thanks a lot for the quick reviews.

I hope I could address all your concerns and suggestions with my latest push.

@chhagedorn: I'm especially happy that you like the tests. As all too often the effort for a good test is much higher than for the fix itself :)

[chhagedorn]

Thanks for doing the changes, they look good to me!

@chhagedorn: I'm especially happy that you like the tests. As all too often the effort for a good test is much higher than for the fix itself :)

Yes, I couldn't agree more to that. It's sometimes underestimated how much time that is needed to come up with a good test. So, I always appreciate the extra effort :)

[openjdk]

@simonis 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:

8275908: Record null_check traps for calls and array_check traps in the interpreter

Reviewed-by: chagedorn, mdoerr

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 25 new commits pushed to the master branch:

• 040b2c5: 8277139: Improve code readability in PredecessorValidator (c1_IR.cpp)
• 3e798dd: 8275330: C2: assert(n->is_Root() || n->is_Region() || n->is_Phi() || n->is_MachMerge() || def_block->dominates(block)) failed: uses must be dominated by definitions
• 99e4bda: 8277417: C1 LIR instruction for load-klass
• 00a6238: 8277508: need to check has_predicated_vectors before calling scalable_predicate_reg_slots
• 3383c0d: 8277659: [TESTBUG] Microbenchmark ThreadOnSpinWaitProducerConsumer.java hangs
• 7e54d06: 8277165: jdeps --multi-release --print-module-deps fails if module-info.class in different versioned directories
• eb4d886: 8277504: Use String.stripTrailing instead of hand-crafted method in SwingUtilities2
• 9879920: 8277825: Remove unused ReferenceProcessorPhaseTimes::_sub_phases_total_time_ms
• f788834: 8277786: G1: Rename log2_card_region_per_heap_region used in G1CardSet
• 3034ae8: 8277631: ZGC: CriticalMetaspaceAllocation asserts
• ... and 15 more: https://git.openjdk.java.net/jdk/compare/d085c2b8a790a5ddfbb01a0ea4edd4051cfb704b...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.

[simonis]

Thanks for the approval @chhagedorn .

I found that the new Decompile.java test failed on linux/x86_32. The reason for this is that 32-bit builds don't include JVMCI and without JMVCI the bimorphic inlining trap is called just bimorphic (in contrast to bimorphic_or_optimized_type_check for JVMCI builds`).

The fix is trivial and I hope your approval is also valid for the latest version :)

[TheRealMDoerr]

Right, non-JVMCI platforms need this fix (also PPC and s390). LGTM, now. We'll retest it.

[chhagedorn]

Good catch! Looks good.

[simonis]

/integrate

[simonis]

Thanks @chhagedorn, @TheRealMDoerr !

[openjdk]

Going to push as commit 40fef23.
Since your change was applied there have been 27 commits pushed to the master branch:

• 3d810ad: 8277411: C2 fast_unlock intrinsic on AArch64 has unnecessary ownership check
• ce0234b: 8277860: PPC: Remove duplicate info != NULL check
• 040b2c5: 8277139: Improve code readability in PredecessorValidator (c1_IR.cpp)
• 3e798dd: 8275330: C2: assert(n->is_Root() || n->is_Region() || n->is_Phi() || n->is_MachMerge() || def_block->dominates(block)) failed: uses must be dominated by definitions
• 99e4bda: 8277417: C1 LIR instruction for load-klass
• 00a6238: 8277508: need to check has_predicated_vectors before calling scalable_predicate_reg_slots
• 3383c0d: 8277659: [TESTBUG] Microbenchmark ThreadOnSpinWaitProducerConsumer.java hangs
• 7e54d06: 8277165: jdeps --multi-release --print-module-deps fails if module-info.class in different versioned directories
• eb4d886: 8277504: Use String.stripTrailing instead of hand-crafted method in SwingUtilities2
• 9879920: 8277825: Remove unused ReferenceProcessorPhaseTimes::_sub_phases_total_time_ms
• ... and 17 more: https://git.openjdk.java.net/jdk/compare/d085c2b8a790a5ddfbb01a0ea4edd4051cfb704b...master

Your commit was automatically rebased without conflicts.

[openjdk]

@simonis Pushed as commit 40fef23.

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

[dholmes-ora]

The new tests are not written correctly and are causing failures in our tier3 CI runs.

If you set an explicit GC on the @run line then you have to ensure no GC option is passed in when running jtreg, else you get two GC's requested and the test fails to run.

https://bugs.openjdk.java.net/browse/JDK-8277878