Hi,
I have a problem that only occurs on nVidia platforms. I have managed to
trace the problem to a certain piece of my code, i.e. the calling of two
functions. The code works under all circumstances on my ATI card, and fails
at the same time/place on two nVidia cards. The error arises during the
build of the kernel. The strange thing is, that when I greatly reduce the
amount of calculations in the functions (less terms in the return statement
- see code below), it might work some times. If i reduce the calculations
slightly but reduce other calculations outside the two functions, it might
work too.
Worthy to note is that the code worked when the elements that the functions
operate on are private memory. The error started to occur when I implemented
work groups and made the elements that it operates on to local (this still
works on ATI).
I tried updating drivers, and have tried both 2011.1beta3 and 2011.1.1, but
the error still occurs.
*Error message:*
Traceback (most recent call last):
File "application.py", line 79, in <module>
[energy,standardDeviation,acceptanceRate,runTime, binCounts] =
getOperatorMean(systemClass, RP, systemOp)
File "src/host.py", line 106, in getOperatorMean
KE = loadKernel(system, BP, operator)
File "src/host.py", line 303, in loadKernel
prg.build(options=buildOptions)
File
"/usr/local/lib/python2.6/dist-packages/pyopencl-2011.1.1-py2.6-linux-x86_64.egg/pyopencl/__init__.py",
line 447, in build
cache_dir=cache_dir)
File
"/usr/local/lib/python2.6/dist-packages/pyopencl-2011.1.1-py2.6-linux-x86_64.egg/pyopencl/cache.py",
line 421, in create_built_program_from_source_cached
ctx, src, options, devices, cache_dir)
File
"/usr/local/lib/python2.6/dist-packages/pyopencl-2011.1.1-py2.6-linux-x86_64.egg/pyopencl/cache.py",
line 346, in _create_built_program_from_source_cached
prg.build(options, [devices[i] for i in to_be_built_indices])
File
"/usr/local/lib/python2.6/dist-packages/pyopencl-2011.1.1-py2.6-linux-x86_64.egg/pyopencl/__init__.py",
line 164, in program_build
raise err
pyopencl.RuntimeError: clBuildProgram failed: build program failure -
Build on <pyopencl.Device 'GeForce GTX 470' at 0x251cb70>:
Error: Code selection failed to select: 0x2ae6010: i1 = add 0x2b73120,
0x2b6e9e0
*Source code for the functions:*
// V - float scalar
// sigma - float scalar
// x - float value from local memory
// y - float value from local memory
inline float operatorFunction(float V, float sigma, float x, float y)
{
float sqrt3 = 1.73205081f;
float invSqrtPi = 0.5641895835f;
float D = 2.0f * sigma * sigma;
float D_inv = 1.0f / D;
float A = 4.0f * x * x;
float B = (x - sqrt3 * y) * (x - sqrt3 * y);
float C = (x + sqrt3 * y) * (x + sqrt3 * y);
return -V * D_inv * invSqrtPi * ((A - D) * native_exp(-A * D_inv) +
(B - D) * native_exp(-B * D_inv) +
(C - D) * native_exp(-C * D_inv)) / sigma;
}
inline float potentialFunction(float V, float sigma, float x, float y)
{
float sqrt3 = 1.73205081f;
float invSqrtPi = 0.5641895835f;
float D_inv = 0.5f/(sigma*sigma);
float A = 4.0f*x*x;
float B = (x-sqrt3*y)*(x-sqrt3*y);
float C = (x+sqrt3*y)*(x+sqrt3*y);
return V * invSqrtPi * (native_exp(-A * D_inv) +
native_exp(-B * D_inv) +
native_exp(-C * D_inv)) / sigma;
}
Thanks,
Patric Holmvall
_______________________________________________
PyOpenCL mailing list
[email protected]
http://lists.tiker.net/listinfo/pyopencl
