[Beignet] cl_khr_fp64 on OpenCL 1.2+

[Yang, Rong R]

Yes, In OpenCL 1.2, using double no longer requires using the pragma cl_khr_fp64. But clang support it from clang 3.7. 
which llvm/clang version do you use? Could you update to llvm/clang 3.7 and try again?

> -----Original Message-----
> From: Beignet [mailto:beignet-bounces at lists.freedesktop.org] On Behalf Of
> Brian Paterni
> Sent: Tuesday, March 1, 2016 22:36
> To: beignet at lists.freedesktop.org
> Subject: [Beignet] cl_khr_fp64 on OpenCL 1.2+
> 
> Hi
> 
> Since the latest beignet release (1.1.1) provided by debian does not support
> double precision floating point, I ended up compiling from source and
> installed the latest git code locally with EXPERIMENTAL_DOUBLE enabled.
> 
> Successfully, clinfo does detect the cl_khr_fp64 extension. However, the
> pyopencl framework I'm working with expects the extension to be included
> as core functionality with OpenCL 1.2+. As an example, the attached minimal
> python code (test-double-record.py) attempts to map a
> numpy.float64 type to an OpenCL C struct, and in doing so, generates a
> minimal kernel to test the struct (tmpvRXvhp.cl). As seen, the kernel only
> enables cl_khr_fp64 if using OpenCL < 1.2, but since I'm using Beignet (opencl
> 1.2), and cl_khr_fp64 is not part of core functionality, I'm met with the
> following error as the generated kernel fails to compile:
> 
>     Traceback (most recent call last):
>       File "./test-double-record.py", line 14, in <module>
>         numpy.dtype([('double_0', numpy.float64)]))
>       File "<decorator-gen-3>", line 2, in match_dtype_to_c_struct
>       File "/usr/lib/python2.7/dist-packages/pytools/__init__.py", line 430, in
> _deco
>         result = func(*args)
>       File "/usr/lib/python2.7/dist-packages/pyopencl/tools.py", line 603, in
> match_dtype_to_c_struct
>         knl = prg.build(devices=[device]).get_size_and_offsets
>       File "/usr/lib/python2.7/dist-packages/pyopencl/__init__.py", line 213, in
> build
>         options=options, source=self._source)
>       File "/usr/lib/python2.7/dist-packages/pyopencl/__init__.py", line 253, in
> _build_and_catch_errors
>         raise err
>     pyopencl.RuntimeError: clBuildProgram failed: build program failure -
> 
>     Build on <pyopencl.Device 'Intel(R) HD Graphics 5500 BroadWell U-
> Processor GT2' on 'Intel Gen OCL Driver' at 0x7f4163b190e0>:
> 
>     stringInput.cl:14:3: error: use of type 'double' requires
> cl_khr_fp64 extension to be enabled
> 
>     (options: -I /usr/lib/python2.7/dist-packages/pyopencl/cl)
>     (source saved as /tmp/tmpNQsE23.cl)
> 
> Given the above, I'm wondering what the best resolution would be? Would a
> request to add cl_khr_fp64 to Beignet's core be possible? Or would a better
> solution exist where pyopencl does not assume cl_khr_fp64 core
> functionality in OpenCL 1.2+?