webrev for running HSAIL same way as PTX from Hotspot

[Doug Simon]

I have integrated this patch [1][2].

On Nov 6, 2013, at 11:11 PM, Caspole, Eric <Eric.Caspole at amd.com> wrote:

> Hi everyone,
> I put a new graal hotspot webrev at
> 
> http://cr.openjdk.java.net/~ecaspole/jvm_kernel_launch.01/webrev/
> 
> Here I made changes to support running HSAIL kernels using the same code path as PTX in Hotspot. I tried to have the same code structure as PTX except that HSAIL arguments are processed differently because HSA has direct access to the java heap.
> 
> I did not do anything with the gpu detection code. I added a -XX:+UseHSAILSimulator option for the time being to use this path rather than the PTX path. These changes will work with the HSA simulator Okra library at
> 
> https://github.com/HSAFoundation/Okra-Interface-to-HSAIL-Simulator
> 
> We are adding new support in that library to work with these hotspot changes. Then you can build the Okra library, put it in the LD_LIBRARY_PATH for the Graal JVM and run HSAIL kernels.
> 
> I think there is a little work to do to more smoothly support the two different offload platforms

I agree. For example in both executeExternalMethodVarargs and executeParallelMethodVarargs, there should be a test on the incoming HotSpotInstalledCode argument to determine which GPU it is for. One solution might be to repurpose the HotSpotInstalledCode.external field to be an ISA identifier (0 meaning host ISA).

-Doug

[1] http://hg.openjdk.java.net/graal/graal/rev/f1a55428a8d7
[2] http://hg.openjdk.java.net/graal/graal/rev/41f0bd213b51