8319980: [JVMCI] libgraal should reuse Thread instances as C2 does

[tkrodriguez]

Reuse Threads instances for compiler threads in the same way C1/C2 do. This has been in use for several months now. mach5 testing is underway.

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Issue

• JDK-8319980: [JVMCI] libgraal should reuse Thread instances as C2 does (Bug - P3)

Reviewers

• Doug Simon (@dougxc - Reviewer) ⚠️ Review applies to c9ec6508
• Vladimir Kozlov (@vnkozlov - Reviewer)

Reviewing

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[openjdk]

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[openjdk]

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

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8319980: [JVMCI] libgraal should reuse Thread instances as C2 does

Reviewed-by: dnsimon, kvn

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At the time when this comment was updated there had been 19 new commits pushed to the master branch:

• c864317: 8320888: Shenandoah: Enable ShenandoahVerifyOptoBarriers in debug builds
• d1e73b1: 8318626: GetClassFields does not filter out ConstantPool.constantPoolOop field
• ea6e92e: 8320945: problemlist tests failing on latest Windows 11 update
• 2584bf8: 8210410: Refactor java.util.Currency:i18n shell tests to plain java tests
• 454b116: 8320942: Only set openjdk-target when cross compiling linux-aarch64
• eb44baf: 8320937: support latest VS2022 MSC_VER in abstract_vm_version.cpp
• 62418c6: 8319444: Unhelpful failure output in TestLegalNotices
• cdd1a6e: 8313816: Accessing jmethodID might lead to spurious crashes
• b65ccff: 8320877: Shenandoah: Remove ShenandoahUnloadClassesFrequency support
• b68356b: 8320806: Augment test/langtools/tools/javac/versions/Versions.java for JDK 22 language changes
• ... and 9 more: https://git.openjdk.org/jdk/compare/335f5dbf628c308fa997fae96e6b1a1e652e05b7...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.

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[mlbridge]

Webrevs

• 02: Full - Incremental (aff529d8)
• 01: Full - Incremental (8c43c7d6)
• 00: Full (c9ec6508)

[vnkozlov]

Is it possible to make condition easy to understand?
From what I finally figure out, we always create thread object for C2 and libgraal. And For Java Graal only for conditions you listed in create.
May be also add comment about that.

[tkrodriguez]

I've simplified the logic so all instances are created up front and the jargraal path can free and recreate them if they go idle. I'm testing this logic now.

[vnkozlov]

Yes, it looks much better if it works for jargraal.

Now this code match following code for C1. If your change works can you factor out it into separate method and pass _compilers[] value? That is only difference I see.

[tkrodriguez]

Yes I'd noticed the duplication too. I'll do that refactor and update the comments to better reflect what's happening now if then test is clean.

[tkrodriguez]

I refactored the code and tested it out. Let me know what you think.

[vnkozlov]

This looks good!
Please, test it in mach5.

[tkrodriguez]

Testing is clean. Thanks!

/integrate

[openjdk]

Going to push as commit da09eab.
Since your change was applied there have been 31 commits pushed to the master branch:

• 33b26f7: 8319123: Implement JEP 461: Stream Gatherers (Preview)
• 04ad98e: 8315458: Implement JEP 463: Implicitly Declared Classes and Instance Main Method (Second Preview)
• 03759e8: 8320304: Refactor and simplify monitor deflation functions
• da7cf25: 8320665: update jdk_core at open/test/jdk/TEST.groups
• c9d15f7: 8321025: Enable Neoverse N1 optimizations for Neoverse V2
• 61653a1: 8320830: [AIX] Dont mix os::dll_load() with direct dlclose() calls
• 8b102ed: 8321063: AArch64: Zero build fails after JDK-8320368
• 6941369: 8320921: GHA: Parallelize hotspot_compiler test jobs
• 0d14636: 8320515: assert(monitor->object_peek() != nullptr) failed: Owned monitors should not have a dead object
• d6b4aa0: 8318157: RISC-V: implement ensureMaterializedForStackWalk intrinsic
• ... and 21 more: https://git.openjdk.org/jdk/compare/335f5dbf628c308fa997fae96e6b1a1e652e05b7...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tkrodriguez Pushed as commit da09eab.

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