RFR: 8295044: Implementation of Foreign Function and Memory API (Second Preview) [v35]

[Alan Bateman]

On Wed, 30 Nov 2022 15:30:40 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

>> This PR contains the API and implementation changes for JEP-434 [1]. A more detailed description of such changes, to avoid repetitions during the review process, is included as a separate comment.
>> 
>> [1] - https://openjdk.org/jeps/434
>
> Maurizio Cimadamore has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 67 additional commits since the last revision:
> 
>  - Merge branch 'master' into PR_20
>  - Address review comment
>  - Polish javadoc:
>    * Make sure that first para of class javadoc is succinct and descriptive
>    * Remove references to "access" var handle or "memory segment view" var handle (just use var handle)
>    * Minor tweak to layout classes javadoc - use `@see` in value layouts instead of a dedicated para.
>    * Other minor typos fixes
>  - Address review comments
>  - * remove unused Scoped interface
>    * re-add trusting of final fields in layout class implementations
>    * Fix BulkOps benchmark, which had alignment issues
>  - Fix bit vs. byte mismatch in test
>  - Fix wrong check in MemorySegment::spliterator/elements
>    (The check which ensures that the segment size is multiple of spliterator element size is bogus)
>  - Address more review comments
>  - Fix bad @throws in MemorySegment::copy methods
>  - Address review comments
>  - ... and 57 more: https://git.openjdk.org/jdk/compare/ddc274f3...8668fb39

src/java.base/share/classes/java/lang/foreign/Arena.java line 135:

> 133:      * @apiNote This operation is not idempotent; that is, closing an already closed arena <em>always</em> results in an
> 134:      * exception being thrown. This reflects a deliberate design choice: arena state transitions should be
> 135:      * manifest in the client code; a failure in any of these transitions reveals a bug in the underlying application

Not important but I'm not sure about the wording here. Maybe you mean "manifested" or "should manifest" ?

src/java.base/share/classes/java/lang/foreign/Arena.java line 155:

> 153: 
> 154:     /**
> 155:      * {@return a new confined arena}

For completeness, this should probably say "a new confined arena owned by the current thread".

-------------

PR: https://git.openjdk.org/jdk/pull/10872