8340733: Add scope for relaxing constraint on JavaCalls from CompilerThread

[tzezula]

JDK-8318694 limited the ability for JVMCI CompilerThreads to make Java upcalls. This is to mitigate against deadlock when an upcall does class loading. Class loading can easily create deadlock situations in -Xcomp or -Xbatch mode.

However, for Truffle, upcalls are unavoidable if Truffle partial evaluation occurs as part of JIT compilation inlining. This occurs when the Graal inliner sees a constant Truffle AST node which allows a Truffle-specific inlining extension to perform Truffle partial evaluation (PE) on the constant. Such PE involves upcalls to the Truffle runtime (running in Java).

This PR provides the escape hatch such that Truffle specific logic can put a compiler thread into "allow Java upcall" mode during the scope of the Truffle logic.

---

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Issue

• JDK-8340733: Add scope for relaxing constraint on JavaCalls from CompilerThread (Enhancement - P4)

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer) Review applies to 81b59f7e
• Doug Simon (@dougxc - Reviewer)

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[openjdk]

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

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8340733: Add scope for relaxing constraint on JavaCalls from CompilerThread

Reviewed-by: dnsimon, kvn

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At the time when this comment was updated there had been 418 new commits pushed to the master branch:

• f77a514: 8343194: Avoid redundant Hashtable.containsKey call in CodeSource.readObject
• 4a70c83: 8343378: Exceptions in javax/management DeadLockTest.java do not cause test failure
• 8d4d589: 8343297: Vector unsigned min/max test are failing with -Xcomp
• 2a4d9d9: 8343379: [BACKOUT] 8343190 GHA: Try building JTReg several times
• 6f6cfe6: 8343380: C2: assert(iff->in(1)->is_OpaqueNotNull()) failed: must be OpaqueNotNull
• cbda758: 8343122: RISC-V: C2: Small improvement for real runtime callouts
• 803612e: 8343121: RISC-V: More accurate max size for C2SafepointPollStub and C2EntryBarrierStub
• b627a41: 8343345: Use -jvmArgsPrepend when running microbenchmarks in RunTests.gmk
• 2932144: 8343305: Remove Indify-dependent microbenchmarks
• 34655c6: 8342544: [macos] jpackage test helper should check for both "--app-image" and "--mac-sign" for signing predefined app image case
• ... and 408 more: https://git.openjdk.org/jdk/compare/0b467e902d591ae9feeec1669918d1588987cd1c...master

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• 05: Full - Incremental (7e0f1a42)
• 04: Full - Incremental (e07d4448)
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• 02: Full - Incremental (f687c82e)
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[vnkozlov]

`/compiler' part of changes is fine.

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[tzezula]

I have simplified the _can_call_java transitions. The only feature in the libjvmci compiler that requires Java calls is Truffle compiler, which utilizes JNI to invoke the Truffle runtime methods. Given that we now have CompilerThreadCanCallJavaScope, which Truffle can use to explicitly enable Java calls, we can safely disable Java calls by default for the libjvmci compiler.

For the Java JVMCI compiler, we still need to permit Java calls to accommodate upcalls to the Graal compiler and for InterpreterRuntime while running the Java JVMCI compiler.

The simplification eliminates the need for TriBool for _can_call_java; it can remain a bool.

[dougxc]

Looks good to me.

[dougxc]

Still look good to me.

[tzezula]

/integrate

[openjdk]

@tzezula
Your change (at version 7e0f1a4) is now ready to be sponsored by a Committer.

[dougxc]

/sponsor

[openjdk]

Going to push as commit 751a914.
Since your change was applied there have been 420 commits pushed to the master branch:

• 7e87c07: 8340116: test/jdk/sun/security/tools/jarsigner/PreserveRawManifestEntryAndDigest.java can fail due to regex
• da0e9e3: 8343333: Parallel: Cleanup comment referring Solaris in MutableNUMASpace
• f77a514: 8343194: Avoid redundant Hashtable.containsKey call in CodeSource.readObject
• 4a70c83: 8343378: Exceptions in javax/management DeadLockTest.java do not cause test failure
• 8d4d589: 8343297: Vector unsigned min/max test are failing with -Xcomp
• 2a4d9d9: 8343379: [BACKOUT] 8343190 GHA: Try building JTReg several times
• 6f6cfe6: 8343380: C2: assert(iff->in(1)->is_OpaqueNotNull()) failed: must be OpaqueNotNull
• cbda758: 8343122: RISC-V: C2: Small improvement for real runtime callouts
• 803612e: 8343121: RISC-V: More accurate max size for C2SafepointPollStub and C2EntryBarrierStub
• b627a41: 8343345: Use -jvmArgsPrepend when running microbenchmarks in RunTests.gmk
• ... and 410 more: https://git.openjdk.org/jdk/compare/0b467e902d591ae9feeec1669918d1588987cd1c...master

Your commit was automatically rebased without conflicts.

[openjdk]

@dougxc @tzezula Pushed as commit 751a914.

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