RFR: 8139457: Array bases are aligned at HeapWord granularity [v6]

[Roman Kennke]

On Thu, 15 Dec 2022 14:00:12 GMT, Stefan Karlsson <stefank at openjdk.org> wrote:

>> Right. I restored the previous code and align-up the base offset. Object arrays in ZGC would not use the leading unaligned 32bits anyway, afaik.
>
> Note that even though the classes are named ObjArrayAllocator, this path is used for primitive arrays as well. I've wanted to change the name, but haven't gotten to it yet.

Oh dear! Ok, I've added a section to properly clean the leading 32 bits if necessary, and verified by running some Z tests with -XX:-UseCompressedClassPointers. Thanks for pointing this out!

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PR: https://git.openjdk.org/jdk/pull/11044