4 Replies Latest reply on Sep 22, 2015 5:39 AM by dipak

    Suspected OpenCL compiler bug

    markr

      I have come across what I am convinced has to be a bug in the OpenCL compiler. I guess this needs to be posted on the OpenCL forum. The bug only occurs in specific circumstances, namely:

      64 bit system

      Relatively complex kernel, using sub-functions, loops  #prama unroll’s etc.

      Device:  Hawaii (290X) (OK on Tahiti – I do not have any other boards readily available to try it on)

      Using the ‘-cl-opt-disable’ option also makes the kernel operate correctly

       

      I am using the latest AMD Driver: 15.200.1062.1004  (03/08/2015)

       

      I have simplified the kernel as much as I can while still exhibiting the issue. I have created a simple self-contained console program that demonstrates the problem. A visual studio solution for VS2013 is in the attached zip file along with further details (see the Read.Me).

        • Re: Suspected OpenCL compiler bug
          pinform

          Hi Mark,

           

          Welcome!

           

          I have white-listed you, so you should be able to directly post in the appropriate developer forum.  As this question seems related to the OpenCL forum, I am moving it there -- the experts there should help.

           

          --Prasad

          • Re: Suspected OpenCL compiler bug
            dipak

            Hi Mark,

            Thanks for reporting the issue and providing the reproducible test-case.

            Yes, it indeed seems a compiler issue. As I checked it using a Hawaii XT card, I got the same observation. I'll file a bug report against this issue.

            BTW, the result seems okay without passing the option ‘-cl-opt-disable’ for both win32 and x64 if the kernel is built for OpenCL 2.0 i.e. with build flag "-cl-std=CL2.0". Could you please check and confirm?

             

            Regards,

            1 of 1 people found this helpful