6.B.3 OpenMP Issues:Mixing Fortran and C

• Bulk of computation is done in Fortran

• Utility routines are in C:

  • IO operations
  • data partitioning routines
  • communication/synchronization operations

• OpenMP-related issues:

  • IF C/OpenMP compiler is not available, data privatization needs to be done through “expansion”.
  • Mix of Fortran and C is implementation dependent

Data privatization in OpenMP/C

#pragma omp thread private (item)

float item;

void x(){

... = item;

}

Data expansion in

absence of OpenMP/C

float item[num_proc];

void x(){

int thread;

thread = omp_get_thread_num();

... = item[thread];

}

Previous slide

Next slide

Back to first slide

View graphic version