topic Re: OpenMP Access violation problem in Intel® Moderncode for Parallel Architectures

OpenMP Access violation problem

elad_golan — Sun, 29 Apr 2007 15:27:26 GMT

Hi,

I am trying to parallelise my code, but I get an access violation error, and my program crashes.

here is my code snippet :

#pragma omp parallel for

for (i=0 ; i

{

if (!EmptyDct)

{

/* Using Intel's IPPi IDCT */

ippiDCT8x8Inv_16s_C1I(DiffMB);

}

I am using Intel compiler and Intel Performance Primitives ver 4.1.

Please help,

Elad

Re: OpenMP Access violation problem

TimP — Sun, 29 Apr 2007 16:40:35 GMT

If your IPP function itself is threaded,that threading would have to be disabled. If IPP were OpenMP threaded, it would be taken care of automatically, but I don't believe this is the case. If your IPP docs don't cover this, you might ask in the IPP forum.

Re: OpenMP Access violation problem

TimP — Mon, 30 Apr 2007 05:22:57 GMT

I note that the IPP dynamic libraries are claimed to be thread safe, not the static ones.

ippiDCT functions are not listed as being OpenMP enabled. In case of doubt about library thread safety, it may be possible to run with Intel Thread Checker, to see if a thread safety problem is found.