[jmm-dev] Non-core-model issues status

[Paul Sandoz]

On Aug 31, 2014, at 4:04 PM, Doug Lea <dl at cs.oswego.edu> wrote:
> 4. We will more uniformly support and spec analogs of C++/C11 moded
> access on fields, array elements, and statics. I had initially
> proposed doing this as a small syntactic extension in JEP193. But I
> think everyone has now settled on instead introducing "VarHandles",
> which are more language-agnostic; basically serving as lighter, more
> broadly applicable, and more efficient variants of
> AtomicXFieldUpdaters that exploit and extend JDK8 MethodHandles. Paul
> Sandoz has been working on this within the Valhalla project, and has
> committed a preliminary version (that I haven't used yet). (See
> http://mail.openjdk.java.net/pipermail/valhalla-dev/2014-August/000111.html)
> They are still not fully spec'ed, and probably cannot be until core
> model settles. But given precedent in C++/C11, I don't expect major
> obstacles in doing so.
> 

The prototype can also support more efficient variants of AtomicXArray classes too, although there is more work to do done, for example to optimize away or strength reduced bounds checks.

Paul.