Updates j.u.c patch and added loop results <was> Re: VarHandle prototype pushed

[Paul Sandoz]

Hi,

I recently:

- merged 9 updates to CompletableFuture and F/J.

- updated the JUC patch converting many j.u.c classes to use VarHandle

  http://cr.openjdk.java.net/~psandoz/varhandles/jdk-varhandle-juc.patch/webrev/

(Still have to do CHM, which i hope does not introduce a bootstrap issue, there is certainly one if MHs are used.)

- uploaded some 166 loop test results run on Dell laptop with an Intel Core i5-2520M CPU @ 2.50GHz x 4. All CPUs were frozen at 2GHz with power management disabled.

  http://cr.openjdk.java.net/~psandoz/varhandles/valhalla-unsafe.166-loops.11-09-2014.txt
  http://cr.openjdk.java.net/~psandoz/varhandles/valhalla-vhs-no-cast.166-loops.12-09-2014.txt
  http://cr.openjdk.java.net/~psandoz/varhandles/valhalla-vhs.166-loops.11-09-2014.txt

Have yet to do any analysis of the results.

Paul.

On Aug 7, 2014, at 10:31 AM, Paul Sandoz <Paul.Sandoz at oracle.com> wrote:

> Hi,
> 
> I have just pushed the VarHandle prototype. More details can be found here:
> 
>  http://cr.openjdk.java.net/~psandoz/varhandles/VarHandle-0.1.md
>  http://cr.openjdk.java.net/~psandoz/varhandles/jvmls14-varHandles.pdf
> 
> Hopefully it won't cause too much disturbance in the "force", but if anyone pulled in-between my pushes to jdk, langtools and hotspot then one will need pull again so everything is in sync. Also, it is unlikely to step on the value type/specialization area as the changes to langtools/hotspot are focused on areas particular to polymorphic signature methods.
> 
> This prototype is sufficient to play around with the API, validate performance and find issues, but it's still very much work in progress.
> 
> I have yet to push a patch to update certain j.u.c classes to replace Unsafe with VarHandle [1]. I am pondering whether to have separate renamed classes, which is nice for a side-to-side comparison in the same code base, but would force test code (e.g. 166 loops tests) to be updated.
> 
> Paul.
> 
> [1] http://cr.openjdk.java.net/~psandoz/varhandles/jdk-varhandle-juc.patch/webrev/