[jdk18] RFR: 8279930: Synthetic cast causes generation of store barriers when using heap segments

[Paul Sandoz]

On Wed, 12 Jan 2022 19:07:00 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

>> yes, that should be harmless
>
> Actually, no, sorry. If I sharpen the type, then `dup` has to cast, so we go back to the original issue.

Ah yes, i see. Maybe it's worth adding a general comment to the class doc of `HeapMemorySegmentImpl` briefly explaining the reasons for use of `Object`.

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PR: https://git.openjdk.java.net/jdk18/pull/97