8373801: Adopt arraycopy OopCopyResult from the lworld branch

[stefank]

In the Valhalla project there's code to restrict nulls in object arrays. In the GC arraycopy barrier we there have to both do null checks in addition to the already existing cast checks. If one of these two failed the code needs to propagate this up through the callers to the code that asked to do the checks. There it will throw the suitable exception. Previously, it was enough to say success or failed, and a boolean was enough. Now we need three states. So the bool was replaced with an OopCopyResult enum.

See: openjdk/valhalla#1792

I propose that we bring this over to the mainline to lower the diff between lworld and the openjdk/jdk.

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Issue

• JDK-8373801: Adopt arraycopy OopCopyResult from the lworld branch (Enhancement - P4)

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)

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[openjdk]

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

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8373801: Adopt arraycopy OopCopyResult from the lworld branch Reviewed-by: tschatzl 

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At the time when this comment was updated there had been 39 new commits pushed to the master branch:

• a31e6e0: 8373593: Support latest VS2026 MSC_VER in abstract_vm_version.cpp
• 8598306: 8364766: C2: Improve Value() of DivI and DivL for non-constant inputs
• e678050: 8367341: C2: apply KnownBits and unsigned bounds to And / Or operations
• ... and 36 more: https://git.openjdk.org/jdk/compare/89e77512fd44b6a0299ab36db15142e7544899f3...master

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[mlbridge]

Webrevs

• 01: Full - Incremental (25c24e3d)
• 00: Full (41ff47bd)

[stefank]

Tier1 testing passes.