[Beignet] Optional features and OpenCL 2.0 support.

[Yichao Yu]

Hi,

I've recently noticed that 64bit floating point numbers are not
supported by beignet but according to a post I have found[1], the GPU
in IvyBridge chip does support fp64. Is this currently limited by the
driver or is there any issue with the hardware as well? Also, I guess
the compiler error message should be changed as well. The beignet
compiler still complain about not having the corresonding #progma
statement when double type is used while fp64 is already a optional
feature rather than an extension for OpenCL 1.2 (yeah I know that the
feature is not supported now but that error message is still wrong and
misleading). The error message when using double (with the #progma
statement) is also quite confusing as well (it talks about overloading
functions not available...)

Since it has been ~1yr after the OpenCL 2.0 release with a lot of
interesting new features, it would be nice to know whether/when it
will be supported by beignet, especially since AMD is planing for
supporting it in Q4 2014. While features like dynamic parallelism
might need new hardware, should it be possible to support sth like svm
with existing hardware.

Just to be clear, the OpenCL 2.0 part is by no mean a feature
request/bug report (on the other hand, it would be nice to see fp64
support if the hardware does have the capability). Since beignet is an
opensource project, I just think this might be the right place to ask
about the capability of the hardware as well as future plan (after
OpenCL 1.2 support).

Yichao Yu

[1] http://www.realworldtech.com/ivy-bridge-gpu/5/