RFR: 8270911: Don't use Access API to access object header word

[Roman Kennke]

On Mon, 19 Jul 2021 14:04:27 GMT, Roman Kennke <rkennke at openjdk.org> wrote:

> Back when Shenandoah required read- and write-barriers on all object accesses, we introduced using the HeapAccess API to access object header words, too. Since JDK 13 (introduction of Shenandoah LRB), this is no longer necessary. I propose to simplify header access by not using the Access API but use ordinary C++ instead.
> 
> (N.b: do we want to get rid of all primitive Access API, too? I would do it.)
> 
> Testing:
>  - [x] tier1
>  - [ ] tier2

Closing this in favour of #5166

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PR: https://git.openjdk.java.net/jdk/pull/4827