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[boxerab]

Hello,

I know this has been asked before, but does anyone know if there are plans

to add these features to OpenCL?

Also, what is the current best practice for implementing

__any(Predicate) and __all(Predicate) methods in OpenCL?

Thanks,

Aaron

[tzachi_cohen]

Hi Aaron,

A Warp or Wavefront are implementation specifics of two Khoronos members and they have no mention in the OCL standard.

There is no high level way to access predicate results of all threads of a Wavefront.

If you write GCN ISA code you can access the VCC flag which holds the results of the most recent predicate for all threads. It is a 64 bit flag , one bit per thread.

[boxerab]

Thanks, Tzachi. It looks like OpenCL 2.0 has these methods:

http://www.khronos.org/registry/cl/specs/opencl-2.0-openclc.pdf#page=152

So, I will wait until the 2.0 release.

On Sat, Jun 14, 2014 at 2:54 PM, tzachi.cohen <developer.forums@amd.com>