8335977: Deoptimization fails with assert "object should be reallocated already"

[JohnTortugo]

Please, review this patch to fix an issue that may occur when serializing debug information related to reduce allocation merges. The problem happens when there are more than one JVMS in a uncommon_trap and a younger JVMS doesn't have the RAM inputs as a local/expression/monitor but an older JVMS does. In that situation the loop at line 1173 of output.cpp will set the is_root property of the ObjectValue to false when processing the younger JVMS even though it may have been set to true when visiting the older JVMS.

Tested on:

• Win, Mac & Linux tier1-4 on x64 & Aarch64.
• CTW with some thousands of jars.

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Progress

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Issue

• JDK-8335977: Deoptimization fails with assert "object should be reallocated already" (Bug - P2)

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