[foreign-jextract] RFR: 8253290: Tweak jextract code to use new MemoryAddress::asSegmentRestricted

[Athijegannathan Sundararajan]

On Thu, 17 Sep 2020 13:50:03 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

> This fixes references to the now-removed MemorySegment::ofNativeRestricted(...).
> 
> The only tricky issue is in RunimeHelper - which has to create an unchecked segment for a global variable and,
> in doing so, it has to keep a reference of the lookup symbol in there, to prevent the library from being unloaded.
> 
> Since the new API doesn't have an explicit way to add an attachment, I've added a simple Runnable impl which wraps a
> symbol, and pass that as a no-op cleanup action to the segment.
> 
> For the records, I believe that creating segments for global vars is tricky enough that there should be a blessed
> (restricted) way to do that in the LibraryLookup.Symbol API.

Marked as reviewed by sundar (Committer).

src/jdk.incubator.jextract/share/classes/jdk/internal/jextract/impl/resources/RuntimeHelper.java.template line 70:

> 68:     }
> 69:
> 70:     static class RunnableHolder implements Runnable {

Should this be called SymbolHolder?

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

PR: https://git.openjdk.java.net/panama-foreign/pull/335